Document and Entity Information - USD ($) $ in Billions	12 Months Ended
Document and Entity Information - USD ($) $ in Billions	Dec. 31, 2019	Feb. 04, 2020	Jun. 28, 2019
Cover [Abstract]
Document type	10-K
Document period end date	Dec. 31, 2019
Amendment flag	false
Entity registrant name	DIODES INC /DEL/
Entity central index key	0000029002
Entity Current Reporting Status	Yes
Entity voluntary filers	No
Current fiscal year end date	--12-31
Entity filer category	Large Accelerated Filer
Entity well known seasoned issuer	Yes
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity common stock shares outstanding		51,206,969
Entity public float			$ 1.5
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Trading Symbol	DIOD
Entity File Number	002-25577
Entity Tax Identification Number	95-2039518
Entity Address, Address Line One	4949 Hedgcoxe Road
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Plano
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75024
City Area Code	972
Local Phone Number	987-3900
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, Par Value $0.66 2/3
Security Exchange Name	NASDAQ
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant’s definitive proxy statement to be filed with the United States Securities and Exchange Commission (“SEC”) pursuant to Regulation 14A in connection with the 2020 annual meeting of stockholders are incorporated by reference into Part III of this Annual Report. The proxy statement will be filed with the SEC not later than 120 days after the registrant’s fiscal year ended December 31, 2019.

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 258,390	$ 241,053
Short-term investments	4,825	7,499
Accounts receivable, net of allowances of $4,866 and $4,102 at December 31, 2019 and 2018, respectively	260,322	228,405
Inventories	236,472	215,435
Prepaid expenses and other current assets	49,950	42,446
Total current assets	809,959	734,838
Property, plant and equipment, net	469,574	446,835
Deferred income tax	17,516	31,652
Goodwill	141,318	132,437
Intangible assets, net	119,523	137,935
Other long-term assets	81,494	42,674
Total assets	1,639,384	1,526,371
Current liabilities:
Line of credit	13,342	10,254
Accounts payable	122,148	117,808
Accrued liabilities	100,571	82,605
Income tax payable	16,156	15,744
Current portion of long-term debt	33,105	27,613
Total current liabilities	285,322	254,024
Long-term debt, net of current portion	64,401	186,143
Deferred tax liabilities	16,333	17,993
Other long-term liabilities	120,545	90,779
Total liabilities	486,601	548,939
Commitments and contingencies (See Note 17)
Stockholders' equity
Preferred stock - par value $1.00 per share; 1,000,000 shares authorized; no shares issued or outstanding
Common stock - par value $0.66 2/3 per share; 70,000,000 shares authorized; 51,206,969 and 50,221,035, issued and outstanding at December 31, 2019 and 2018, respectively	35,111	34,454
Additional paid-in capital	427,262	399,915
Retained earnings	789,958	636,708
Treasury stock, at cost, 1,457,206 shares held at December 31, 2019 and 2018	(37,768)	(37,768)
Accumulated other comprehensive loss	(108,139)	(101,846)
Total stockholders' equity	1,106,424	931,463
Noncontrolling interest	46,359	45,969
Total equity	1,152,783	977,432
Total liabilities and stockholders' equity	$ 1,639,384	$ 1,526,371

CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$ 4,866	$ 4,102
Preferred stock par value	$ 1.00	$ 1.00
Preferred stock shares authorized	1,000,000	1,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock par value	$ 0.66	$ 0.66
Common stock shares authorized	70,000,000	70,000,000
Common stock shares issued	51,206,969	50,221,035
Common stock shares outstanding	51,206,969	50,221,035
Treasury stock, shares	1,457,206	1,457,206

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net sales	$ 1,249,130	$ 1,213,989	$ 1,054,204
Cost of goods sold	783,323	778,713	697,428
Gross profit	465,807	435,276	356,776
Operating expenses
Selling, general and administrative	181,343	176,197	168,590
Research and development	88,517	86,286	77,877
Amortization of acquisition-related intangible assets	18,041	18,351	18,798
Impairment of fixed assets		390	2,211
Restructuring		206	10,137
Gain on disposal of fixed assets	(24,429)	(636)	(245)
Other operating expense (income)	1,727		(1)
Total operating expenses	265,199	280,794	277,367
Income from operations	200,608	154,482	79,409
Other income (expense)
Interest income	2,189	1,978	1,475
Interest expense	(7,893)	(9,901)	(13,448)
Foreign currency loss, net	(3,737)	(3,701)	(7,995)
Other income	7,079	7,104	3,150
Total other expense	(2,362)	(4,520)	(16,818)
Income before income taxes and noncontrolling interest	198,246	149,962	62,591
Income tax provision	44,131	44,556	62,325
Net income	154,115	105,406	266
Less: net income attributable to noncontrolling interest	(865)	(1,385)	(2,071)
Net income (loss) attributable to common stockholders	$ 153,250	$ 104,021	$ (1,805)
Earnings (loss) per share attributable to common stockholders
Basic	$ 3.02	$ 2.09	$ (0.04)
Diluted	$ 2.96	$ 2.04	$ (0.04)
Number of shares used in computation
Basic	50,787	49,841	48,824
Diluted	51,860	50,935	48,824

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract]
Net income	$ 154,115	$ 105,406	$ 266
Unrealized (loss) gain on defined benefit plan, net of tax	(4,142)	3,440	(4,897)
Unrealized (loss) gain on interest rate swap, net of tax	(3,652)	737	1,018
Unrealized foreign currency gain (loss), net of tax	1,501	(22,543)	33,065
Comprehensive income	147,822	87,040	29,452
Less: Comprehensive income attributable to noncontrolling interest	(865)	(1,385)	(2,071)
Total comprehensive income attributable to common stockholders	$ 146,957	$ 85,655	$ 27,381

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3000-108585

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591552-111686

+ Details

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Total Diodes Incorporated Stockholders' Equity	Noncontrolling Interest
BALANCE at Dec. 31, 2016	$ 820,467	$ 32,919	$ (29,023)	$ 354,574	$ 530,215	$ (112,666)	$ 776,019	$ 44,448
Common stock shares beginning at Dec. 31, 2016		49,376,000	(1,157,000)
Total comprehensive income	29,452				(1,805)	29,186	27,381	2,071
Noncontrolling interests	476			(165)			(165)	641
Dividends to noncontrolling interest	(4,746)							(4,746)
Adoption of new accounting standard, ASU 2016-09	5,048			771	4,277		5,048
Common stock issued for share-based plans	13,606	$ 808		12,798			13,606
Common stock issued for share-based plans, shares		1,211,000
Stock buyback	$ (8,745)		$ (8,745)				(8,745)
Stock buyback, shares	(300,000)		(300,000)
Share-based compensation	$ 18,638			18,638			18,638
Tax related to net share settlement	(278)			(278)			(278)
BALANCE at Dec. 31, 2017	873,918	$ 33,727	$ (37,768)	386,338	532,687	(83,480)	831,504	42,414
Common stock shares ending at Dec. 31, 2017		50,587,000	(1,457,000)
Total comprehensive income	87,040				104,021	(18,366)	85,655	1,385
Contributions from noncontrolling interests	4,902							4,902
Dividends to noncontrolling interest	(2,732)							(2,732)
Common stock issued for share-based plans	$ 4,861	$ 727		4,134			4,861
Common stock issued for share-based plans, shares		1,091,000
Stock buyback, shares	0
Share-based compensation	$ 20,736			20,736			20,736
Tax related to net share settlement	(11,293)			(11,293)			(11,293)
BALANCE at Dec. 31, 2018	$ 977,432	$ 34,454	$ (37,768)	399,915	636,708	(101,846)	931,463	45,969
Common stock shares ending at Dec. 31, 2018	50,221,035	51,678,000	(1,457,000)
Total comprehensive income	$ 147,822				153,250	(6,293)	146,957	865
Contributions from noncontrolling interests	3,343							3,343
Dividends to noncontrolling interest	(3,818)							(3,818)
Common stock issued for share-based plans	$ 11,901	$ 657		11,244			11,901
Common stock issued for share-based plans, shares		986,000
Stock buyback, shares	0
Share-based compensation	$ 20,535			20,535			20,535
Tax related to net share settlement	(4,432)			(4,432)			(4,432)
BALANCE at Dec. 31, 2019	$ 1,152,783	$ 35,111	$ (37,768)	$ 427,262	$ 789,958	$ (108,139)	$ 1,106,424	$ 46,359
Common stock shares ending at Dec. 31, 2019	51,206,969	52,664,000	(1,457,000)

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net income	$ 154,115	$ 105,406	$ 266
Adjustments to reconcile net income to net cash provided by operating activities, net of effects of acquisitions:
Depreciation	91,543	86,291	76,883
Amortization of intangibles	18,041	18,353	18,798
Amortization of debt issuance costs	521	522	514
Share-based compensation	20,535	20,736	18,609
Gain on disposal of property, plant and equipment	(24,429)	(636)	1,969
Deferred income taxes	9,904	3,674	25,326
Other	(187)	(2,335)	(1,814)
Changes in operating assets:
Accounts receivable	(30,775)	(29,478)	22,261
Inventories	(11,325)	(2,154)	(17,199)
Prepaid expenses and other current assets	(6,630)	(11,119)	1,494
Changes in operating liabilities:
Accounts payable	3,513	9,977	17,313
Accrued liabilities	7,369	(13,445)	13,079
Other liabilities	(2,694)	345	4,495
Income taxes payable (refundable)	271	(571)	(871)
Net cash and cash equivalents provided by operating activities	229,772	185,566	181,123
Investing Activities
Acquisitions, net of cash acquired	(33,028)	(41)
Purchases of short-term investments	(19,271)	(15,901)	(12,205)
Sales of short-term investments	21,847	12,576	38,600
Purchases of property, plant and equipment	(98,505)	(87,507)	(111,161)
Proceeds from sales of property, plant and equipment	29,366	429	1,219
Receipt of subsidies and grants			6,968
Other	(835)	1,500	(2,333)
Net cash and cash equivalents used in investing activities	(100,426)	(88,944)	(78,912)
Financing Activities
Advances on lines of credit and short-term debt	9,954	9,151	3,375
Repayments on lines of credit and short-term debt	(7,362)	(2,797)	(2,391)
Taxes related to net share settlement	(4,432)	(11,294)	(278)
Net proceeds from the issuance of common stock	11,901	4,862	13,606
Proceeds from long-term debt	405,540	465,656	44,500
Debt issuance costs	(223)		(111)
Repayments of long-term debt	(522,860)	(522,473)	(204,374)
Repayments of finance lease obligations	(1,082)	1,198	(587)
Purchase of treasury stock			(8,745)
Capital contribution from noncontrolling interest		6,255
Dividend distribution to noncontrolling interest	(3,818)	(2,694)	(5,754)
Other	(50)	225	2,575
Net cash and cash equivalents used in financing activities	(112,432)	(51,911)	(158,184)
Effect of exchange rate changes on cash and cash equivalents, including restricted cash	760	(8,078)	11,461
Increase (decrease) in cash and cash equivalents, including restricted cash	17,674	36,633	(44,512)
Cash and cash equivalents, beginning of year, including restricted cash	241,833	205,200	249,712
Cash and cash equivalents, end of year, including restricted cash	259,507	241,833	205,200
Cash paid during the year for:
Interest	7,235	9,962	13,547
Income taxes	37,158	33,265	30,447
Non-cash activities:
(Increase) decrease property, plant and equipment purchased on accounts payable	$ 2,260	$ 7,766	(14,081)
Noncontrolling Interest
Non-cash activities:
Decrease (increase) in dividend accrued for noncontrolling interest			$ 1,008

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 258,390	$ 241,053	$ 203,820
Restricted cash (included in other current assets)	1,117	780	1,380
Total cash, cash equivalents and restricted cash	$ 259,507	$ 241,833	$ 205,200

Summary of Operations and Significant Accounting Policies

12 Months Ended

Dec. 31, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Summary of Operations and Significant Accounting Policies

Note 1 – Summary of Operations and Significant Accounting Policies

Nature of operations

Diodes Incorporated, together with its subsidiaries (collectively, the “Company,” “we” or “our”) (Nasdaq: DIOD), is a leading global manufacturer and supplier of high-quality, application-specific standard products within the broad discrete, logic, analog and mixed-signal semiconductor markets. We serve the consumer electronics, computing, communications, industrial, and automotive markets. Our products include diodes, rectifiers, transistors, MOSFETs, protection devices, function-specific arrays, single gate logic, amplifiers and comparators, Hall-effect and temperature sensors, power management devices, including LED drivers, AC-DC converters and controllers, DC-DC switching and linear voltage regulators, and voltage references along with special function devices, such as USB power switches, load switches, voltage supervisors, and motor controllers. We also have timing, connectivity, switching, and signal integrity solutions for high-speed signals. Our corporate headquarters and Americas’ sales offices are located in Plano, Texas and Milpitas, California. Design, marketing, and engineering centers are located in Plano; Milpitas; Taipei, Taoyuan City and Zhubei City, Taiwan; Oldham, England; and Neuhaus, Germany. Our wafer fabrication facilities are located in Oldham and Shanghai, China and Greenock, Scotland. We have assembly and test facilities located in Shanghai, Jinan and Chengdu, China, as well as in Hong Kong, Neuhaus and Taipei. Additional engineering, research and development, sales, warehouse, and logistics offices are located in Taipei; Hong Kong; Oldham; Shanghai; Shenzhen and Yangzhou, China; Seongnam-si, South Korea; Munich, Germany; and Tokyo, Japan, with support offices throughout the world.

Significant Accounting Policies

Principles of consolidation – The consolidated financial statements include the accounts of Diodes Incorporated, its wholly-owned subsidiaries and its controlled majority-owned subsidiaries. We account for equity investments in companies over which we have the ability to exercise significant influence, but do not hold a controlling interest, under the equity method, and we record our proportionate share of income or losses in Interest and other, net in the consolidated statements of income. All significant intercompany balances and transactions have been eliminated.

Use of estimates – The preparation of financial statements in conformity with generally accepted accounting principles in the United States of America (“GAAP”) requires that management make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The level of uncertainty in estimates and assumptions increases with the length of time until the underlying transactions are completed. Actual results may differ from these estimates in amounts that may be material to the consolidated financial statements and accompanying notes.

Revenue recognition – Effective January 1, 2018, we adopted the comprehensive new revenue recognition standard ASC 606. The details of the significant changes to our accounting policies resulting from the adoption of the new standard are set out below. We adopted the standard using a modified retrospective method. There was no change in our revenue reported for the twelve months ended December 30, 2017. The adoption of this standard did not have a material impact on our condensed consolidated financial position, reported revenue, results of operations or cash flows as of and for the twelve months ended December 31, 2018.

ASC 606 defines a performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and under ASC 606 is the unit of account. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Generally speaking, our performance obligations represent a promise to transfer various semiconductor products, and have the same pattern of revenue recognition. Our performance obligations are satisfied at either a point in time, or over time as work progresses. The vast majority of our revenue from products and services is accounted for at a point in time. Substantially all of our revenue in direct and Distributor sales is recognized at a point in time. Further, the payment terms on our sales are based on negotiations with our customers.

Our customers can order different types of semiconductors in a single contract (purchase order), and each line on a purchase order represents a separate performance obligation. Depending on the terms of an arrangement, we may also be responsible for shipping and handling activities. In accordance with ASC 606-10-25-18B, we have elected to account for shipping and handling as activities to fulfill our promise to transfer the good(s). As such, shipping and handling activities do not represent a separate performance obligation, and are accrued as a fulfillment cost. Further, although we offer warranties on our products, our warranties are considered to be assurance-type in nature and do not cover anything beyond ensuring that the product is functioning as intended. Based on the guidance in ASC 606, assurance-type warranties do not represent separate performance obligations; therefore, the primary performance obligation in the majority of our contracts is the delivery of a specific good through the purchase order submitted by our customer.

We record allowances/reserves for a number of items. The following items are the largest dollar items for which we record allowances/reserves, with ship and debit making up the vast majority: (i) ship and debit, which arise when we issue credit to certain distributors upon their shipments to their end customers; (ii) stock rotation, which are contractual obligations that permit certain distributors, up to four times a year, to return a portion of their inventory based on historical shipments to them in exchange for an equal and offsetting order; and (iii) price protection, which arise when market conditions cause average selling prices to decrease and we issue credit to certain distributors on their inventory. Ship and debit reserves are recorded as a reduction to net sales with a corresponding reduction to accounts receivable. Stock rotation reserves and price protection reserves are recorded as a reduction to net sales with a corresponding increase in accrued liabilities.

We also assess our customer’s ability and intention to pay, which is based on a variety of factors including our customer’s historical payment experience, their financial condition and the condition of the global economy and financial markets. Payment terms and conditions typically vary depending on negotiations with the customer.

Net sales are reduced in the period of sale for estimates of product returns and other allowances including distributor adjustments, which were approximately $163.9 million, $158.8 million and $158.1 million in 2019, 2018 and 2017, respectively.

Product warranty – We generally warrant our products for a period of one year from the date of sale. Historically, warranty expense has not been material.

Cash, cash equivalents, and short-term investments – We consider all highly liquid investments with maturity of three months or less at the date of purchase to be cash equivalents. We currently maintain substantially all of our day-to-day operating cash balances with major financial institutions. We hold short-term investments consisting of time deposits, which are highly liquid with maturity dates greater than three months at the date of purchase. Generally, we can access these investments in a relatively short amount of time but in doing so we generally forfeit a portion of interest income. See Note 3 below for additional information regarding fair value of financial instruments.

Allowance for doubtful accounts – We evaluate the collectability of our accounts receivable based upon a combination of factors, including the current business environment and historical experience. If we are aware of a customer’s inability to meet its financial obligations, we record an allowance to reduce the receivable to the amount we reasonably believe will be collected from the customer. For all other customers, we record an allowance based upon the amount of time the receivables are past due. If actual accounts receivable collections differ from these estimates, an adjustment to the allowance may be necessary with a resulting effect on operating expense. Accounts receivable are presented net of valuation allowance, which were approximately $4.9 million at December 31, 2019 and $4.1 million at December 31, 2018.

Inventories – Inventories are stated at the lower of cost or net realizable value. Cost is determined principally by the first-in, first-out method. Cost includes materials, labor, and manufacturing overhead related to the purchase and production of inventories. Any write-down of inventory to the lower of cost or net realizable value at the close of a fiscal period creates a new cost basis that subsequently would not be marked up based on changes in underlying facts and circumstances. On an on-going basis, we evaluate inventory for obsolescence and slow-moving items. This evaluation includes analysis of sales levels, sales projections, and purchases by item, as well as raw material usage related to our manufacturing facilities. If our review indicates a reduction in utility below carrying value, we reduce inventory to a new cost basis. If future demand or market conditions are different than our current estimates, an inventory adjustment to write down inventory may be required, and would be reflected in cost of goods sold in the period the revision is made.

Property, plant and equipment – Purchased property, plant and equipment is recorded at historical cost, and property, plant and equipment acquired in a business combination is recorded at fair value on the date of acquisition. Property, plant and equipment is depreciated using straight-line methods over the estimated useful lives, which range from 20 to 55 years for buildings and 3 to 10 years for machinery and equipment. The estimated lives of leasehold improvements range from 3 to 5 years, and are amortized over the shorter of the remaining lease term or their estimated useful lives.

Goodwill and other indefinite lived intangible assets – Goodwill and indefinite lived assets are tested for impairment on an annual basis or when an event or changes in circumstances indicate that its carrying value may not be recoverable. Goodwill impairment is tested at the reporting unit level, which is defined as an operating segment or one level below the operating segment. Diodes has one operating segment. No goodwill impairment occurred in 2019, 2018, or 2017. Goodwill is reviewed for impairment using either a qualitative assessment or a quantitative goodwill impairment test. If we choose to perform a qualitative assessment and determine the fair value more likely than not exceeds the carrying value, no further evaluation is necessary. When we perform the quantitative goodwill impairment test, we compare fair value to carrying value, which includes goodwill. If fair value exceeds carrying value, the goodwill is not considered impaired. If the carrying value is higher than the fair value, the difference would be recognized as an impairment loss.

Impairment of long-lived assets – Our long-lived assets are reviewed whenever events or changes in circumstances indicate that the carrying value may not be recoverable. We consider assets to be impaired if the carrying value exceeds the undiscounted projected cash flows from operations. If impairment exists, the assets are written down to fair value or to the projected discounted cash flows from related operations. As of December 31, 2019, we expect the remaining carrying value of assets to be recoverable. During 2017, we recognized an impairment of long-lived assets related to the KFAB fixed assets. See Note 19 below for additional information related to the KFAB shut down.

Business combinations – The Company recognizes all (and only) the assets acquired and liabilities assumed in the transaction and establishes the acquisition-date fair value as the measurement objective for all assets acquired and liabilities assumed in a business combination. Certain provisions prescribe, among other things, the determination of acquisition-date fair value of consideration paid in a business combination (including contingent consideration) and the exclusion of transaction and acquisition-related restructuring costs from acquisition accounting. During the normal course of business the Company makes acquisitions. In the event that an individual acquisition (or an aggregate of acquisitions) is material, appropriate disclosure of such acquisition activity is provided. See Note 20 for additional information regarding business combinations.

Income taxes – Income taxes are accounted for using an asset and liability approach whereby deferred tax assets and liabilities are recorded for differences in the financial reporting bases and tax bases of our assets and liabilities. If it is more likely than not that some portion of deferred tax assets will not be realized, a valuation allowance is recorded.

GAAP prescribes a comprehensive model for how companies should recognize, measure, present, and disclose in their financial statements uncertain tax positions taken or expected to be taken on a tax return. Tax positions shall initially be recognized in the financial statements when it is more likely than not the position will be sustained upon examination by the tax authorities. Such tax positions shall initially and subsequently be measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement with the tax authority assuming full knowledge of the position and all relevant facts. All deferred income taxes are classified as noncurrent assets or noncurrent liabilities on the consolidated balance sheet as of December 31, 2019 and 2018, respectively.

Research and development costs – Internally-developed research and development costs are expensed as incurred. Acquired in-process research and development (“IPR&D”) is capitalized as an indefinite-lived intangible asset and evaluated periodically for impairment. When the project is completed, an expected life is determined and the IPR&D is amortized as an expense over the expected life.

Shipping and handling costs – Shipping and handling costs for products shipped to customers, which are included in selling, general and administrative expenses, were approximately $13.9 million, $14.8 million and $15.2 million for the twelve months ended December 31, 2019, 2018 and 2017, respectively.

Concentration of credit risk – Financial instruments, which potentially subject us to concentrations of credit risk, include trade accounts receivable. Credit risk is limited by the dispersion of our customers over various geographic areas, operating primarily in electronics manufacturing and distribution. We perform a credit evaluation of new customers and monitor the accounts receivable aging of our existing customers. Generally we require no collateral from our customers and historically credit losses have been insignificant.

We currently maintain substantially all of our day-to-day cash balances and short-term investments with major financial institutions. Cash balances are usually in excess of Federal and/or foreign deposit insurance limits.

Valuation of financial instruments – The carrying value of our financial instruments, including cash and cash equivalents, short-term investments, accounts receivable, accounts payable, credit line, and long-term debt approximate fair value due to their current market conditions, maturity dates and other factors.

Share-based compensation – We use the Black-Scholes-Merton model to determine the fair value of stock options on the date of grant and recognize compensation expense for stock options on a straight-line basis. Restricted stock grants are measured based on the fair market value of the underlying stock on the date of grant and compensation expense is recognized on a straight-line basis over the requisite four-year service period. Performance stock units are measured based on the fair market value of the underlying stock on the date of grant and compensation expense is recognized over the three-year performance period, with adjustments made to the expense to recognize the probable payout percentage.

The amount of compensation expense recognized using the Black-Scholes-Merton model requires us to exercise judgment and make assumptions relating to the factors that determine the fair value of our stock option grants. The fair value calculated by this model is a function of several factors, including the grant price, the expected future volatility, the expected term of the option and the risk-free interest rate of the option. The expected term and expected future volatility of the options require judgment. In addition, we

estimate the expected forfeiture rate and only recognize expense for those stock options expected to vest. We estimate the forfeiture rate based on historical experience, and to the extent our actual forfeiture rate is different from our estimate, share-based compensation expense is adjusted accordingly.

Treasury stock – Under a program authorized by our board of directors we have purchased shares of our common stock. These shares are recorded as treasury stock, at cost, as a reduction to stockholder’ equity.

Functional currencies and foreign currency translation – We translate the assets and liabilities of our non-U.S. dollar functional currency subsidiaries into U.S. dollars using exchange rates on the balance sheet date. Net sales and expense for these subsidiaries are translated at the weighted-average exchange rate during the period presented. Resulting translation adjustments are recorded as a separate component of accumulated other comprehensive income or loss within stockholders’ equity in the consolidated balance sheets. Included in other income are foreign exchange losses of approximately $3.7 million for both twelve month periods ended December, 31, 2019 and 2018 and approximately $ 8.0 million for the twelve months ended December 31, 2017.

Defined benefit plan – We maintain plans covering certain of our employees in the U.K. The overfunded or underfunded status of pension and postretirement benefit plans are recognized on the balance sheet. Actuarial gains and losses, and prior service costs or credits, are recognized in other comprehensive income (loss), net of tax effects, until they are amortized as a component of net periodic benefit cost. For financial reporting purposes, the net pension and supplemental retirement benefit obligations and the related periodic pension costs are calculated based upon, among other things, assumptions of the discount rate for plan obligations, estimated return on pension plan assets and mortality rates. These obligations and related periodic costs are measured using actuarial techniques and assumptions. The projected unit credit method is the actuarial cost method used to compute the pension liabilities and related expenses. The expected long-term return on plan assets was determined based on historical and expected future returns of the various asset classes. The plan’s investment policy includes a mandate to diversify assets and invest in a variety of asset classes to achieve its expected long-term return and is currently invested in a variety of funds representing most standard equity and debt security classes. Trustees of the plan may make changes at any time.

Noncontrolling interest - Noncontrolling interest primarily relates to the minority investors’ share of the earnings of certain China and Taiwan subsidiaries. Noncontrolling interests are a separate component of equity and not a liability. Increases or decreases in noncontrolling interest, due to changes in our ownership interest of the subsidiaries that leave control intact, are recorded as equity transactions. The noncontrolling interest in our subsidiaries and their equity balances are reported separately in the consolidated financial statements, and activities of these subsidiaries are included therein.

Contingencies – From time to time, we may be involved in a variety of legal matters that arise in the normal course of business. Based on information available, we evaluate the likelihood of potential outcomes. We record and disclose the appropriate liability when the amount is deemed probable and reasonably estimable. In addition, we do not accrue for estimated legal fees and other directly related costs as they are expensed as incurred.

Comprehensive income (loss) – GAAP generally requires that recognized revenue, expenses, gains and losses be included in net income. Although certain changes in assets and liabilities are reported as separate components of the equity section of the consolidated balance sheet, such items, along with net income, are components of comprehensive income or loss. The components of accumulated other comprehensive income or loss include foreign currency translation adjustments and unrealized gain or loss on defined benefit plan. Accumulated other comprehensive loss was approximately $108.1 million, $101.8 million and $83.5 million at December 31, 2019, 2018 and 2017, respectively.

As of December 31, the accumulated balance for each component of comprehensive income is as follows:

	2019			2018
Unrealized foreign currency losses	$	(63,053	)	$	(64,553	)
Unrealized gain on interest rate swap, net of tax	$	(391	)	$	3,261
Unrealized loss on defined benefit plan	$	(44,695	)	$	(40,554	)

Reclassifications – Certain immaterial amounts from prior periods have been reclassified to conform to the current years’ presentation.

Recently Issued Accounting Pronouncements

The Financial Accounting Standards Board (“FASB”) issued the following Accounting Standards Updates (“ASU”) which could have potential impact to the Company’s financial statements:

Recently Adopted Standards

ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”) – In February 2016, the FASB issued ASU 2016-02, which amends the accounting treatment for leases and requires, among other things, lessees to recognize a right-of-use (“ROU”) asset and lease liability for most lease arrangements. The amendments were effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company adopted ASU 2016-02 on January 1, 2019, using the modified retrospective transition approach, under which financial results reported in periods prior to 2018 are unchanged. We elected the following allowed practical expedients as permitted under the transition guidance within the new standard:

•

Not record leases with an initial term of 12 months or less on the balance sheet;

•

Not separate non-lease components of leases from the lease components; and

•

Not reassess (1) the definition of a lease, (2) lease classification, and (3) initial direct costs for existing leases during transition.

Upon adoption of ASU 2016-02, the Company recorded ROU assets of $68.3 million, including land-use rights of $17.1 million previously recorded in other assets and $2.5 million previously recorded in property, plant and equipment and ROU liabilities of $50.4 million. For additional information related to the Company’s leases, see Note 9.

The Company determines if an arrangement is a lease at inception. ROU assets are included in Other assets in the Company’s condensed consolidated balance sheets. Current lease liabilities are included in Accrued liabilities and other and long-term lease liabilities are included in Other long-term liabilities, in our condensed consolidated balance sheets.

ROU assets represent the Company’s right to use an underlying asset for the lease term, and lease liabilities represent its obligation to make lease payments arising from the lease. ROU assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. To determine the present value of the lease payments, we estimate our incremental borrowing rate based on information available at the lease commencement date.

The Company’s lease term includes options to extend the lease when it is reasonably certain that it will exercise that option. Leases with a term of 12 months or less are not recorded on the balance sheet. Our leases typically do not contain any residual value guarantees. For real estate, we account for the lease and non-lease components as a single lease component.

ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting ("ASU 2018-07") - In June 2018, the FASB issued ASU 2018-07, which simplifies several aspects of the accounting for nonemployee share-based payment transactions resulting from expanding the scope of Topic 718, Compensation—Stock Compensation, to include share-based payment transactions for acquiring goods and services from nonemployees. ASU 2018-07 was effective for the Company on January 1, 2019. The adoption of this standard did not have a material effect on our condensed consolidated financial statements or disclosures.

ASU No. 2017-12 - Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities (“ASU 2017-12”) -In August 2017, the FASB issued ASU No. 2017-12 to better align hedge accounting with risk management strategies, and as a result, more hedging strategies will be eligible for hedge accounting. Public business entities will have until the end of the first quarter in which a hedge is designated to perform an initial assessment of a hedge’s effectiveness. After initial qualification, the new guidance permits a qualitative effectiveness assessment for certain hedges instead of a quantitative test if the company can reasonably support an expectation of high effectiveness throughout the term of the hedge. An initial quantitative test to establish that the hedge relationship is highly effective is still required. The amendments are effective for fiscal years beginning after December 15, 2018, and the Company adopted the new standard January 1, 2019. The new standard had no impact on the Company’s financial statements.

On January 1, 2019, the Company adopted ASU No. 2018-16, “Derivatives and Hedging (Topic 815): Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap (OIS) Rate as a Benchmark Interest Rate for Hedge Accounting Purposes”. The amendments in this ASU permit the use of the OIS rate based on SOFR as a U.S. benchmark interest rate for hedge accounting purposes under ASC 815, in addition to the currently permissible benchmark interest rates. This ASU provides the Company the ability to utilize the OIS rate based on SOFR as the benchmark interest rate on certain hedges of interest rate risk. The new standard had no impact on the Company’s financial statements.

Standards Effective in Future Years

The FASB has issued the following relevant standards, effective in future years, which are not expected to have a material impact on our consolidated condensed financial statements:

Standard No.	Standard Name	Standard Effective Date
2018-13	Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement	January 1, 2020
2018-14	Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans	January 1, 2020

In April 2019, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, that clarifies and improves areas of guidance related to the recently issued standards on credit losses (ASU 2016-13), hedging (ASU 2017-12), and recognition and measurement of financial instruments (ASU 2016-01). The amendments generally have the same effective dates as their related standards. If already adopted, the amendments of ASU 2016-01 and ASU 2016-13 are effective for fiscal years beginning after December 15, 2019 and the amendments of ASU 2017-12 are effective as of the beginning of the Company’s next annual reporting period; early adoption is permitted. The Company is evaluating the impact of the adoption of these standards.

Earnings Per Share

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Earnings Per Share

Note 2 – Earnings per Share

Basic earnings per share is calculated by dividing net earnings attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is calculated similarly but includes potential dilution from the exercise of stock options and stock awards, except when the effect would be anti-dilutive. Earnings per share are computed using the “treasury stock method.”

	Twelve Months Ended December 31,
	2019		2018		2017
Earnings (numerator)
Net income (loss) attributable to common stockholders	$	153,250	$	104,021	$	(1,805	)

Shares (denominator)
Weighted average common shares outstanding (basic)		50,787		49,841		48,824
Dilutive effect of stock options and stock awards outstanding		1,073		1,094		-
Adjusted weighted average common shares outstanding (diluted)		51,860		50,935		48,824

Earnings (loss) per share attributable to common stockholders
Basic	$	3.02	$	2.09	$	(0.04	)
Diluted	$	2.96	$	2.04	$	(0.04	)

Stock options and stock awards excluded from EPS calculation because their inclusion would be anti-dilutive (In thousands)		101		1,103		3,508

Fair Value Measurements

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 3 – Fair Value Measurements

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.

We use valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities. The income approach uses valuation techniques to convert future amounts, such as cash flows or earnings, to a single present amount on a discounted basis. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement costs). Valuation techniques should be consistently applied. Inputs to valuation techniques refer to the assumptions that market participants would use in pricing the asset or liability. Inputs may be observable, meaning those that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources, or unobservable, meaning those that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. These two types of inputs create a three-tier fair value hierarchy that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows:

Level 1 Inputs - Unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.

Level 2 Inputs - Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (for example, interest rates, volatilities, prepayment speeds, loss severities, credit risks and default rates) or inputs that are derived principally from or corroborated by observable market data by correlation or other means.

Level 3 Inputs - Significant unobservable inputs that reflect an entity’s own assumptions that market participants would use in pricing the assets or liabilities.

As of December 31, 2019, we had short-term investments. Trading securities held at December 31, 2019, were purchased on the open market and unrealized gains and losses are included in Other income (expense). The trading securities are valued under the fair value hierarchy using Level 1 Inputs. Short-term investments consist of investments such as time deposits, which are highly liquid with maturity dates greater than three months at the date of purchase. Generally, we can access these short-term investments in a relatively short amount of time but in doing so we generally forfeit a portion of earned and future interest income. Deferred compensation investments consist of the Company’s stock, mutual funds and cash. See Note 13 for additional information related to our deferred compensation program and Note 18 for additional information related to our interest rate swaps and foreign currency hedges. The short-term investments and deferred compensation investments are valued under the fair value hierarchy using Level 1 and Level 2 Inputs.

Financial assets and liabilities carried at fair value as of December 31, 2019, are classified in the following table:

Description	Fair Market Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Changes in Fair Values Included in Current Period Earnings
Short-term investments	$	4,825	$	4,825	$	-	$	-	$	-
Interest rate swaps and collars		51		-		51		-		-
Deferred compensation investments		12,912		2,534		10,378		-		-

Financial assets and liabilities carried at fair value as of December 31, 2018 are classified in the following table:

Description	Fair Market Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Changes in Fair Values Included in Current Period Earnings
Short-term investments	$	7,499	$	5,594	$	1,905	$	-	$	-
Interest rate swap assets		4,731		-		4,731		-		-
Deferred compensation investments		10,104		3,377		6,727		-		-

Certain financial assets and financial liabilities are measured at fair value on a non-recurring basis; that is, the instruments are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). We believe our long-term debt under our revolving credit facility approximates fair value and is valued under the fair value hierarchy using Level 2 Inputs. Financial assets and financial liabilities measured at fair value on a non-recurring basis were not significant at December 31, 2019 and 2018.

We also are responsible for a pension plan in the U.K. that holds investments carried at fair value. See Note 13 for additional information related to these pension plan investments.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment [Abstract]

Property, Plant and Equipment

Note 5 – Property, Plant and Equipment

Property, plant and equipment at December 31 were:

	2019			2018
Buildings and leasehold improvements	$	228,522		$	208,184
Machinery and equipment		863,771			817,202
		1,092,293			1,025,386
Less: Accumulated depreciation and amortization		(706,658	)		(635,969	)
		385,635			389,417
Construction in-progress		30,747			16,886
Land		53,192			40,532
	$	469,574		$	446,835

Depreciation and amortization of property, plant and equipment was $91.5 million, $86.3 million and $76.9 million for the years ended December 31, 2019, 2018 and 2017, respectively. At December 31, 2018, we had capital lease obligations totaling approximately $2.1 million, included in Other current liabilities and Other long-term liabilities on the balance sheet. See Note 9 for information related to our lease liabilities as of December 31, 2019. During the fourth quarter of 2019 the Company recorded a $24.3 million gain realized upon selling land. The land was acquired in a previous period in anticipation of building a new corporate headquarters building.

Intangible Assets

12 Months Ended

Dec. 31, 2019

Intangible Assets Net Excluding Goodwill [Abstract]

Intangible Assets

Note 6 – Intangible Assets

Intangible assets subject to amortization at December 31 were as follows:

December 31, 2019
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	12,931	$	(10,634	)	$	(254	)	$	2,043
Developed product technology	2-10 years		159,129		(77,915	)		(7,857	)		73,357
Customer relationships	7-12 years		62,093		(30,138	)		(1,682	)		30,273
Software license and other	3-4 years		5,822		(5,765	)		(49	)		8
Total amortized intangible assets			239,975		(124,452	)		(9,842	)		105,681
Intangible assets with indefinite lives
In process research and development	Indefinite		4,580		-			-			4,580
Trademarks and trade names	Indefinite		10,303		-			(1,041	)		9,262
Total Intangible assets with indefinite lives			14,883		-			(1,041	)		13,842
Total intangible assets		$	254,858	$	(124,452	)	$	(10,883	)	$	119,523

December 31, 2018
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	11,823	$	(9,848	)	$	(307	)	$	1,668
Developed product technology	2-10 years		159,129		(66,112	)		(6,221	)		86,796
Customer relationships	7-12 years		62,093		(24,737	)		(1,689	)		35,667
Software license and other	3-4 years		5,822		(5,713	)		(64	)		45
Total amortized intangible assets			238,867		(106,410	)		(8,281	)		124,176
Intangible assets with indefinite lives
In process research and development	Indefinite		4,580		-			-			4,580
Trademarks and trade names	Indefinite		10,303		-			(1,124	)		9,179
Total Intangible assets with indefinite lives			14,883		-			(1,124	)		13,759
Total intangible assets		$	253,750	$	(106,410	)	$	(9,405	)	$	137,935

Amortization expense related to intangible assets subject to amortization was $18.0 million, $18.4 million and $18.8 million for the years ended December 31, 2019, 2018 and 2017, respectively. In process research and development is transferred to amortized intangible assets at the time the product becomes viable.

The schedule below sets future amortization expense of our currently owned intangible assets:

2020	$	15,671
2021		15,065
2022		14,451
2023		14,186
2024		13,831
2025 and thereafter		32,477
Total	$	105,681

Goodwill

12 Months Ended

Dec. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill

Note 7 – Goodwill

Changes in goodwill for the years ended December 31, were as follows:

Balance at December 31, 2017	$	134,187
Acquisitions:
ERIS acquisition of Yea Shin Technology Corporation		1,029
Foreign currency translation adjustment		(2,779	)
Balance at December 31, 2018	$	132,437
Acquisitions:
Wafer fabrication in Greenock, Scotland		931
Canyon Investment		1,671
ERIS acquisition of Yea Shin Technology Corporation		4,320
Foreign currency translation adjustment		1,959
Balance at December 31, 2019	$	141,318

Bank Credit Agreements and Other Short-Term and Long-Term Debt

12 Months Ended

Dec. 31, 2019

Long Term Debt By Current And Noncurrent [Abstract]

Bank Credit Agreements and Other Short-Term and Long-Term Debt

Note 8 – Bank Credit Agreements and Other Short-term and Long-term Debt

Short-term debt

Our Asia subsidiaries maintain credit facilities with several financial institutions through our foreign entities worldwide totaling $126.6 million. Other than two Taiwanese credit facilities that are collateralized by assets, our foreign credit lines are unsecured, uncommitted, repayable on demand, terminable by the lender at any time and contain no restrictive covenants. These credit facilities bear interest at LIBOR or similar indices plus a specified margin. Interest payments are due quarterly on outstanding amounts under the credit lines. The unused and available credit under the various facilities as of December 31, 2019, was approximately $111.8 million, net of a $13.3 million advanced under our foreign credit lines and $1.4 million credit used for import and export guarantee.

Long-term debt

We currently have a U.S. banking credit facility (the “U.S. Credit Facility”) under which we may draw up to $250 million on a revolving basis, in addition to a $250 million term loan. The U.S. Credit Facility matures October 26, 2021. The remaining portion of the term loan included in the U.S. Credit Facility is repayable in part through quarterly installments that increase over time from $6.3 million per quarter in the first three quarters of 2019 to $9.4 million per quarter in the final year of the U.S. Credit Facility. We may, from time to time, request increases in the aggregate commitments under the U.S. Credit Facility of up to $200 million, subject to the lenders electing to increase their commitments or by means of the addition of new lenders, and subject to at least half of each increase in aggregate commitments being in the form of term loans, with the remaining amount of each increase being an increase in the amount of the revolving portion of the U.S. Credit Facility. The U.S. Credit Facility bears interest at LIBOR or similar indices plus a specified margin. The U.S. Credit Facility contains certain financial and non-financial covenants, including, but not limited to, a maximum consolidated leverage ratio, a minimum consolidated fixed charge coverage ratio, and restrictions on liens, indebtedness, investments, fundamental changes, dispositions, and restricted payments (including dividends and share repurchases). At December 31, 2019, we owed $75.2 million under the U.S. Credit Facility, all of which was outstanding under the term loan. The obligations of the Company and the other borrowers under the U.S. Credit Facility are secured by substantially all of the assets of the Company, including controlling interests in its first-tier subsidiaries, and by specified assets of certain of its subsidiaries. In addition to our credit lines, our 51% owned subsidiary, ERIS Technology Corporation (“ERIS”), borrowed $23.5 million on a long-term basis from local Taiwan banks in order to make an investment. The first loan of $4.3 million matures in 2033, while the second loan of $19.2 million matures in 2024.

Long-term debt balances as of December 31, consist of the following:

	2019			2018
Notes payable to Bank of Taiwan, original principal amount of TWD 140 million, fixed interest rate of 1.3%, matures June 28, 2033.	$	4,242		$	4,442
Notes payable to Yuan Ta Bank, original principal amount of TWD 113 million, fixed interest rate of 1.7%, matured on January 29, 2019.		-			749
Notes payable to China Trust Bank, original principal of TWD 576 million, fixed interest rate of 1.7%, matures May 27, 2024		19,212

Term loan and revolver		75,187			210,000
Total long-term debt		98,641			215,191
Less: Current portion		(33,105	)		(27,613	)
Less: Unamortized debt issuance costs		(1,135	)		(1,435	)
Long-term debt, net of current portion	$	64,401		$	186,143

The table below sets forth the annual contractual maturities of long-term debt at December 31, 2019:

2020	$	33,102
2021		43,620
2022		4,903
2023		1,571
2024		12,689
2025 and thereafter		2,756
Total long-term debt	$	98,641

Leases

12 Months Ended

Dec. 31, 2019

Leases [Abstract]

Leases

Note 9 – Leases

The Company leases certain assets used in its business, including land, buildings and equipment. These leased assets are used for operational and administrative purposes.

The components of lease expense are set forth in the table below:

	Twelve Months Ended
	December 31, 2019
Operating lease expense	$	14,824
Finance lease expense:
Amortization of assets		978
Interest on lease liabilities		48
Short-term lease expense		336
Variable lease expense		2,663
Total lease expense	$	18,849

The table below sets forth supplemental balance sheet information related to leases:

	December 31, 2019
Operating leases:
Operating lease ROU assets	$	57,427

Current operating lease liabilities		12,554
Noncurrent operating lease liabilities		27,545
Total operating lease liabilities	$	40,099

Finance leases:
Finance lease ROU assets	$	3,396
Accumulated amortization		(1,924	)
Finance lease ROU assets, net	$	1,472

Current finance lease liabilities	$	903
Non-current finance lease liabilities		138
Total finance lease liabilities	$	1,041

Weighted average remaining lease term (in years):
Operating leases		4.4
Finance leases		1.3

Weighted average discount rate:
Operating leases		3.8	%
Finance leases		3.0	%

The table below sets forth supplemental cash flow and other information related to leases:

	Twelve Months Ended
	December 31, 2019
Cash paid for the amounts included in the measurements of lease liabilities:
Operating cash outflows from operating leases	$	18,325
Operating cash outflows from finance leases		48
Financing cash outflow from finance leases		1,082

ROU assets obtained in exchange for lease liabilities incurred:
Operating leases		3,956

The table below sets forth information about lease liability maturities:

	December 31, 2019
	Operating Leases			Finance Leases
2020	$	13,779		$	922
2021		9,766			138
2022		8,276			-
2023		4,537			-
2024		2,433			-
2025		2,328			-
2026 and thereafter		2,573			-
Total lease payments		43,692			1,060
Less: imputed interest		(3,593	)		(19	)
Total lease obligations		40,099			1,041
Less: current obligations		(12,554	)		(903	)
Long-term lease obligations	$	27,545		$	138

Accrued Liabilities and Other Long-Term Liabilities

12 Months Ended

Dec. 31, 2019

Accrued Liabilities Current And Noncurrent [Abstract]

Accrued Liabilities and Other Long-Term Liabilities

Note 10 – Accrued Liabilities and Other Long-Term Liabilities

Accrued liabilities and other current liabilities at December 31 were:

	2019		2018
Accrued expenses	$	33,733	$	28,170
Compensation and payroll taxes		34,043		33,632
Equipment purchases		10,167		12,568
Operating lease		12,554		-
Finance lease		903		-
Accrued pricing adjustments		5,617		3,591
Accrued professional services		3,258		3,242
Other		296		1,402
	$	100,571	$	82,605

Other long-term liabilities at December 31 were:

	2019		2018
Accrued defined benefit plan	$	28,795	$	26,349
Unrecognized tax benefits		28,215		27,711
Operating lease		27,545		-
Finance lease		138		-
Deferred grans and subsidy		12,774		15,359
Deferred compensation		12,166		9,091
Tax contingencies		8,631		8,475
Other		2,281		3,794
	$	120,545	$	90,779

Income Taxes

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

Note 12 – Income Taxes

The table below sets forth our (loss) income before taxes for the years ended December 31:

Income (loss) before income taxes	2019		2018			2017
U.S.	$	73,352	$	(24,141	)	$	(72,668	)
Foreign		124,894		174,103			135,259
Total	$	198,246	$	149,962		$	62,591

The table below sets forth the components of our income tax provision (benefit) for the years ended December 31:

	2019		2018			2017
Current tax provision
Federal	$	259	$	-		$	-
Foreign		28,829		42,726			31,820
State		92		24			7
		29,180		42,750			31,827
Deferred tax provision (benefit)
Federal		886		2,400			30,186
Foreign		11,994		(3,107	)		(2,352	)
State		30		56			(8	)
		12,910		(651	)		27,826

Liability for unrecognized tax benefits		2,041		2,457			2,672
Total income tax provision	$	44,131	$	44,556		$	62,325

Effective Tax Rate Reconciliation

The table below sets forth a reconciliation between the effective tax rate and the statutory tax rates for the years ended December 31:

	2019						2018						2017
				Percent						Percent						Percent
				of pretax						of pretax						of pretax
	Amount			earnings*			Amount			earnings*			Amount			earnings*
Federal tax	$	41,632			21.0		$	31,488			21.0		$	21,907			35.0
State income taxes, net of federal tax provision		1,389			0.7			(375	)		(0.3	)		(15	)		-
Foreign income taxed at lower tax rates		(5,786	)		(2.9	)		(2,844	)		(1.9	)		(23,515	)		(37.6	)
U.S. tax impact of foreign operations		(3,340	)		(1.7	)		4,140			2.8			6,726			10.7
Foreign withholding taxes		22,685			11.4			10,962			7.3			4,343			6.9
Research and development		(3,686	)		(1.9	)		(3,541	)		(2.4	)		(2,643	)		(4.2	)
Liability for unrecognized tax benefits		2,041			1.0			2,457			1.6			2,672			4.3
Valuation allowance		(10,563	)		(5.3	)		(379	)		(0.3	)		2,077			3.3
Employee stock-based compensation		(52	)		(0.0	)		(2,154	)		(1.4	)		1,537			2.5
U.S. Tax Cuts and Jobs Act		-			-			2,762			1.8			45,908			73.4
Other		(189	)		(0.1	)		2,040			1.4			3,328			5.3
Income tax provision	$	44,131			22.3		$	44,556			29.7		$	62,325			99.6

*	The sum of the amounts in the table may not equal to the effective tax rate due to rounding.

Uncertain Tax Positions

In accordance with the provisions related to accounting for uncertainty in income taxes, we recognize the benefit of a tax position if the position is “more likely than not” to prevail upon examination by the relevant tax authority. The table below sets forth a reconciliation of the beginning and ending amount of unrecognized tax benefits:

	2019			2018			2017
Balance at January 1,	$	32,209		$	30,581		$	28,849
Additions based on tax positions related to the current year		9,274			4,667			3,492
Additions for prior year tax positions		39			-			863
Reductions for prior year tax positions		(5,870	)		(3,039	)		(2,623	)
Balance at December 31,	$	35,652		$	32,209		$	30,581

If the $35.7 million of unrecognized tax benefits as of December 31, 2019, is recognized, approximately $33.5 million would affect the effective tax rate. It is reasonably possible that the amount of the unrecognized benefit with respect to certain of our unrecognized tax positions will significantly increase or decrease within the next 12 months. These changes may be the result of settlements of ongoing audits or competent authority proceedings. At this time, an estimate of the range of the reasonably possible outcomes cannot be made.

We file income tax returns in the U.S. federal jurisdiction and in various state and foreign jurisdictions. We are no longer subject to U.S. federal income tax examinations by tax authorities for tax years before 2012 or tax year 2015. We are no longer subject to China income tax examinations by tax authorities for tax years before 2009. With respect to state and local jurisdictions and countries outside of the U.S., with limited exceptions, we are no longer subject to income tax audits for years before 2014. Although the outcome of tax audits is always uncertain, we believe that adequate amounts of tax, interest and penalties, if any, have been provided for in our reserve for any adjustments that may result from future tax audits. We recognize accrued interest and penalties, if any, related to unrecognized tax benefits in interest expense. We had an immaterial amount of accrued interest and penalties at December 31, 2019, 2018 and 2017.

Deferred Taxes

The table below sets forth our deferred tax assets and liabilities as of December 31:

	2019			2018
Deferred tax assets
Inventory cost	$	10,423		$	7,974
Accrued expenses and accounts receivable		4,420			1,866
Foreign tax credits		5,848			17,600
Research and development tax credits		16,263			15,456
Net operating loss carryforwards		24,139			9,635
Lease obligations		3,773			-
Accrued pension		4,629			4,294
Share based compensation and others		7,805			9,972
		77,300			66,797
Valuation allowances		(29,414	)		(25,941	)
Total deferred tax assets, non-current		47,886			40,856
Deferred tax liabilities
Plant, equipment and intangible assets		(13,816	)		(16,661	)
Right of use assets		(4,008	)		-
Outside basis differences and others		(23,648	)		(7,267	)
Total deferred tax liabilities, non-current		(41,472	)		(23,928	)
Net deferred tax assets	$	6,414		$	16,928

ASU No. 2013-11 provides that an entity is required to present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. The $1.2 million net deferred tax assets presented in the balance sheet as of December 31, 2019, is net of $5.2 million of unrecognized tax benefits. The $6.4 million and $16.9 million net deferred tax asset presented above for December 31, 2019 and 2018, respectively, is prior to the net balance sheet presentation required by ASU 2013-11.

At December 31, 2019, we had federal and state tax credit and research credit carryforwards of approximately $14 million and $8 million, respectively, which are available to offset future income tax liabilities. The federal tax credit carryforwards begin to expire in 2023 and the state tax credit carryforwards will begin to expire in 2020. Consistent with prior years, we determined that it is more likely than not that our state research credit carryforwards will expire before they are utilized. During 2019 we determined that it is more likely than not that our federal tax credit carryforwards will be utilized before expiration. We released the previously recorded valuation allowances as a credit to income tax expense. The valuation allowances recorded against the related deferred tax assets totaled $8 million and $19 million as of December 31, 2019 and 2018, respectively.

At December 31, 2019, we had state net operating loss (“NOL”) carryforwards of approximately $1 million, and foreign NOL carryforwards of $110 million which are available to offset future taxable income. The state NOL carryforward will begin to expire in 2020. We determined that it is more likely than not that the state NOL carryforwards will expire before they are fully utilized and recorded a full valuation allowance on the related deferred tax assets. The foreign NOL carryforwards will begin to expire in 2020. We determined that it is more likely than not that a portion of the foreign NOL carryforwards will expire before they are fully utilized. The valuation allowances recorded against the related deferred tax assets totaled $19 million and $7 million as of December 31, 2019 and 2018, respectively.

Supplemental Information

Our undistributed foreign earnings continue to be indefinitely reinvested in foreign operations, with limited exceptions related to earnings of European and Asian subsidiaries. As of December 31, 2019, we had undistributed earnings from non-U.S. operations of approximately $913 million (including approximately $115 million of restricted earnings, which are not available for dividends). Undistributed earnings of our China subsidiaries comprise $425 million of this total. Additional Chinese withholding taxes of approximately $46 million would be required should the $425 million of such earnings be distributed out of China as dividends.

The impact of tax holidays decreased our tax expense by approximately $3.1 million, $1.6 million and $3.7 million for the years ended December 31, 2019, 2018 and 2017, respectively. The benefit of the tax holidays on basic and diluted earnings per share was $0.06, $0.03 and $0.08 for the twelve months ended December 31, 2019, 2018 and 2017, respectively.

Employee Benefit Plans

12 Months Ended

Dec. 31, 2019

Compensation And Retirement Disclosure [Abstract]

Employee Benefit Plans

Note 13 – Employee Benefit Plans

Defined Benefit Plan

In connection with the Zetex acquisition, we adopted a contributory defined benefit plan that covers certain employees in the U.K. The defined benefit plan is closed to new entrants and frozen with respect to future benefit accruals. The retirement benefit is based on the final average compensation and service of each eligible employee. We determined the fair value of the defined benefit plan assets and utilize an annual measurement date of December 31. At subsequent measurement dates, defined benefit plan assets will be determined based on fair value. Defined benefit plan assets consist of a diverse range of listed and unlisted securities including corporate bonds and mutual funds and are denominated in the currency in which the benefits will be paid and that have terms to maturity approximating the terms of the related pension liability. The net pension and supplemental retirement benefit obligations and the related periodic costs are based on, among other things, assumptions of the discount rate, estimated return on plan assets and mortality rates. These obligations and related periodic costs are measured using actuarial techniques and assumptions. The projected unit credit method is the actuarial cost method used to compute the pension liabilities and related expenses. All unrecognized actuarial gains and losses, prior service costs and accumulated other comprehensive income are eliminated and the balance sheet liability is set equal to the funded status of the defined benefit plan at acquisition date. In October 2018, a U.K. High Court ruling required pension plans, subject to guaranteed minimum pension rules to amend their pension plan formulas to equalize benefits for men and women to adjust for unequal results previously calculated. The U.K. High Court ruling went on to require pension plans to make back payments subject to plan rule limitations, with interest applied at one percentage point over the Bank of England base rate. The guarantee equalization payment was allowed for by increasing the pension liability. Our portion of the total equalization amount was approximately £0.5 million (or approximately $0.7 million based on GBP: USD exchange rate of 1.33).

The table below sets forth net periodic benefit costs of the plan for the twelve months ended December 31:

	Defined Benefit Plan
	2019			2018
Components of net periodic benefit cost:
Service cost	$	256		$	267
Interest cost		4,069			4,151
Recognized actuarial loss		1,546			2,625
Expected return on plan assets		(7,511	)		(7,339	)
Prior service cost		55			-
Net periodic benefit cost	$	(1,585	)	$	(296	)

The table below sets forth the benefit obligation, the fair value of plan assets, and the funded status as of December 31:

	Defined Benefit Plan
	2019			2018
Change in benefit obligation:
Beginning balance	$	141,104		$	166,063
Service cost		255			267
Interest cost		4,045			4,151
Actuarial loss (gain)		11,214			(9,827	)
Benefits paid		(4,158	)		(3,625	)
Settlements		-			(7,471	)
Currency changes		6,220			(8,454	)
Benefit obligation at December 31	$	158,680		$	141,104

Change in plan assets:
Beginning balance - fair value	$	117,162		$	134,234
Employer contribution		2,629			2,796
Actual return on plan assets		11,791			(2,084	)
Benefits paid		(4,158	)		(3,625	)
Settlements		-			(6,731	)
Currency changes		5,197			(7,428	)
Fair value of plan assets at December 31	$	132,621		$	117,162
Underfunded status at December 31	$	(26,059	)	$	(23,942	)

Based on an actuarial study performed as of December 31, 2019, the plan is underfunded by approximately $26.1 million and the liability is reflected in our consolidated balance sheets as a noncurrent liability and the amount recognized in accumulated other comprehensive loss was approximately $44.7 million.

We apply the “10% corridor” approach to amortize unrecognized actuarial gains (losses). Under this approach, only actuarial gains (losses) that exceed 10% of the greater of the projected benefit obligation or the market-related value of the plan assets are amortized. For the twelve months ended December 31, 2019, the plan’s total recognized loss increased by approximately $5.1 million. The variance between the actual and expected return to plan assets during 2019 decreased the total unrecognized net loss by approximately $4.3 million. The total unrecognized net loss is more than 10% of the projected benefit obligation and 10% of the plan assets. Therefore, the excess amount will be amortized over the average term to retirement of plan participants, not yet in receipt of pension, which as of December 31, 2019, the average term was approximately 10.5 years. The following weighted-average assumptions were used to determine net periodic benefit costs for the twelve months ended December 31:

	2019			2018
Discount rate		2.9	%		2.6	%
Expected long-term return on plan assets		6.4	%		5.6	%

The following weighted-average assumption was used to determine the benefit obligations at December 31:

	2019				2018
Discount rate		2.0	%			2.9	%

The expected long-term return on plan assets was determined based on historical and expected future returns of the various asset classes. The plan’s investment policy includes a mandate to diversify assets and invest in a variety of asset classes to achieve its expected long-term return and is currently invested in a variety of funds representing most standard equity and debt security classes. Trustees of the plan may make changes at any time. The table below sets forth the plan asset allocations of the assets in the plan and expected long-term return by asset category:

Asset category	Expected long-term return			Asset allocation
Growth assets		7.8	%		70	%
Hedging assets		1.3	%		27	%
Cash		0.8	%		3	%
Total		5.6	%		100	%

Benefit plan payments are primarily made from funded benefit plan trusts and current assets. The table below sets forth the expected future benefit payments, including future benefit accrual, as of December 31, 2019:

2020	$	4,030
2021		4,592
2022		4,913
2023		5,335
2024		5,668
2025-2029		29,846

We adopted a payment plan with the trustees of the defined benefit plan, in which we would make annual contributions each year through 2030, of approximately GBP 2 million (approximately $2.7 million based on a GBP:USD exchange rate of 1.33). The annual contributions were expected to meet the deficit disclosed in the plan as of April 5, 2013 by December 31, 2030. The trustees are required to review the funding position every three years. Following the pension plan funding valuation as at March 31, 2019 the trustees and the Company have been in discussions regarding a recovery plan would result in a plan to recover the deficit by January 1, 2029. Moving the recovery plan from a 2030 deadline to a 2029 deadline could cause us to increase our contributions. This plan has not been finalized.

The defined benefit plan’s investment strategy is to invest 65% in growth strategy assets and 35% in hedging strategy assets. The growth strategy consists of a highly diversified set of assets, and the hedging component is designed to hedge a significant proportion of the plan’s interest and inflation rate risks. The overall strategy is designed to return a long-term return of 2.6% p.a. above the liability benchmark which is broadly equal to changes in the plan’s liabilities.

The plan’s trustees appoint fund managers to carry out all the day-to-day functions relating to the management of the fund and its administration. The fund managers must invest their portion of the plan’s assets in accordance with their investment manager agreement agreed by the trustees. The trustees are responsible for agreeing these investment manager agreements and for deciding on the portion of the plan’s assets that will be invested with each fund manager. When making decisions, the trustees take advice from experts including the plan’s actuary and also have the option to consult with the Company.

The following table summarizes the major categories of the plan assets:

	December 31, 2019
Asset category	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	14,057	$	-	$	-	$	14,057
Equity securities:
U.K.		-		683		-		683
Overseas equities		-		5,909		-		5,909
Emerging markets		-		11,413		-		11,413
Fixed income securities:
Government bonds		-		5,160		-		5,160
Non-government bonds		-		9,906		-		9,906
Index-linked securities:
U.K. treasury securities		-		166		-		166
Other types of investments
Hedge funds		-		39,710		-		39,710
Property		-		3,224		-		3,224
Liability-driven investments		-		42,014		-		42,014
Other		-		379		-		379
Total	$	14,057	$	118,564	$	-	$	132,621

Fair value is taken to mean the bid value of securities, as supplied by the fund managers. All the plan’s securities are publicly traded and highly liquid. The plan does not hold any Level 3 securities. See Note 3 for additional information regarding fair value and Levels 1, 2 and 3.

The investment manager agreements require the fund managers to invest in a diverse range of stocks and bonds across each particular asset class. The stocks held by the plan in a particular asset class should therefore match closely the underlying stocks in the relevant index. We believe that this leads to minimal concentration of risk within each asset class; although we recognize that some asset classes are inherently more risky than others.

We also have pension plans in Asia for which the benefit obligation, fair value of the plan assets and the funded status amounts are immaterial and therefore, not included in the amounts or assumptions above.

401(k) Retirement Plan

We maintain a 401(k) retirement plan (the “Plan”) for the benefit of qualified employees at our U.S. locations. Employees who participate may elect to make salary deferral contributions to the Plan up to 100% of the employees’ eligible payroll subject to annual Internal Revenue Code maximum limitations. We currently make a matching contribution of $1 for every $2 contributed by the participant up to 6% (3% maximum matching) of the participant’s eligible payroll, which vests over an initial four years. In addition, we may make a discretionary contribution to the entire qualified employee pool, in accordance with the Plan.

As stipulated by the regulations of China, we maintain a retirement plan pursuant to the local municipal government for the employees in China. We are required to make contributions to the retirement plan at a rate between 10% and 22% of the employee’s eligible payroll. Pursuant to the Taiwan Labor Standard Law and Factory Law, we maintain a retirement plan for the employees in Taiwan, whereby we make contributions at a rate of 6% of the employee’s eligible payroll.

For the years ended December 31, 2019, 2018 and 2017, total amounts expensed under these plans were approximately $16.3 million, $17.0 million and $14.8 million, respectively.

Deferred Compensation Plan

We maintain a Non-Qualified Deferred Compensation Plan (the “Deferred Compensation Plan”) for executive officers, key employees and members of our Board of Directors. The Deferred Compensation Plan allows eligible participants to defer the receipt of eligible compensation, including equity awards, until designated future dates. We offset our obligations under the Deferred Compensation Plan by investing in the actual underlying investments. At December 31, 2019 these investments are classified as trading securities and are carried at fair value. At December 31, 2019, these investments totaled approximately $12.9 million. All gains and losses in these investments are materially offset by corresponding gains and losses in the deferred compensation plan liabilities.

Share-Based Compensation

12 Months Ended

Dec. 31, 2019

Share Based Compensation [Abstract]

Share-Based Compensation

Note 14 – Share-Based Compensation

The table below sets forth the line items where share-based compensation expense was recorded for the twelve months ended December 31:

	2019		2018		2017
Cost of goods sold	$	925	$	362	$	645
Selling, general and administrative expense		16,687		17,395		15,130
Research and development expense		2,923		2,979		2,834
Total share-based compensation expense	$	20,535	$	20,736	$	18,609

The table below sets forth share-based compensation expense by type for the twelve months ended December 31:

	2019		2018		2017
Stock options	$	-	$	274	$	934
Share grants		20,535		20,462		17,675
Total share-based compensation expense	$	20,535	$	20,736	$	18,609

In May 2013, our stockholders approved our 2013 Equity Incentive Plan (“2013 Plan”). Since the approval of the 2013 Plan, all stock options are granted under the 2013 Plan, and we will not grant any further stock options under our 2001 Plan. Stock options under the 2013 Plan generally vest in equal annual installments over a four-year period and expire eight years after the grant date. The number of shares originally authorized to be awarded under the 2013 Plan was 6 million shares. In May 2017, our stockholders approved an amendment to the 2013 Plan, authorizing and additional 6 million shares to be awarded, bringing the total shares authorized to be awarded under the 2013 Plan to 12 million shares.

Share-based compensation expense for stock options granted in previous years was calculated on the date of grant using the Black-Scholes-Merton option-pricing model. No stock options were granted in any of the periods presented.

Total cash received from option exercises was approximately $11.9 million, $4.9 million and $13.6 million during 2019, 2018 and 2017, respectively.

At December 31, 2019, there was no unrecognized compensation expense related to unvested options.

The table below sets forth a summary of activity in our stock option plan:

Stock Options	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2016		1,833			23.08
Exercised		(581	)		23.42
Forfeited or expired		(24	)		26.87
Outstanding at December 31, 2017		1,228			22.85
Exercised		(240	)		20.28
Outstanding at December 31, 2018		988			23.47
Exercised		(524	)		22.68			$	10,600
Outstanding and Exercisable at December 31, 2019		464			24.37		2.0	$	14,849

The table below sets forth information about stock options outstanding at December 31, 2019:

Plan

Range of Exercise Prices

Number Exercisable

Weighted Average Remaining Contractual Life

(Years)

Weighted Average Exercise Price

2001 Plan

$15.05-29.21

259

2.0

23.17

2013 Plan

$23.35-27.92

205

2.0

25.91

Share Grants – Restricted stock awards and restricted stock units generally vest in equal annual installments over a four-year period. All new grants are granted under the 2013 Plan, and there will be no additional share grants under the 2001 Plan. Restricted stock grants are measured based on the fair market value of the underlying stock on the date of grant and compensation expense is recognized on a straight-line basis over the requisite four-year service period.

Performance stock units (“PSUs”) are measured based on the fair market value of the underlying stock on the date of grant and compensation expense is recognized over the three-year performance period, with adjustments made to the expense to recognize the probable payout percentage. PSUs will vest upon the Company achieving a cumulative 3-year non-GAAP operating income target for the applicable periods.

The table below sets forth a summary of our non-vested share grants in 2019, 2018 and 2017:

Restricted and Performance Stock Grants	Shares			Weighted Average Grant Date Fair Value ($)		Aggregate Intrinsic Value
Nonvested at December 31, 2016		2,620			21.31
Granted		746			25.23
Vested		(645	)		21.89
Forfeited		(441	)		22.31
Nonvested at December 31, 2017		2,280			22.24
Granted		646			32.06
Vested		(1,213	)		21.39
Forfeited		(46	)		24.72
Nonvested at December 31, 2018		1,667			26.68
Granted		670			38.15
Vested		(573	)		24.90	$	20,682
Forfeited		(67	)		30.44
Nonvested at December 31, 2019		1,697			31.71	$	95,687

During 2017, the Company modified a performance-based award previously granted to our Chief Executive Officer. The effect was to replace a performance-based grant covering 700,000 shares of the Company’s common stock with a performance-based grant covering 62,905 shares of the Company’s common stock and a restricted stock grant covering 62,905 of the Company’s common stock. If certain performance criteria are met for the performance-based grant, Dr. Lu will receive 200% of that award or 125,810 shares. The incremental expense if Dr. Lu received 200% of the performance-based grant award is approximately $3.3 million. The incremental expense of the restricted stock grant is approximately $1.7 million. During 2018, we modified previously granted stock option and stock awards for two corporate officers who retired. The result of the modification was the acceleration of the vesting of 7,500 stock options and 79,720 stock awards for the corporate officers. The incremental expense recorded for this modification was approximately $1.8 million, which was expensed in SG&A during 2018.

The total unrecognized share-based compensation expense as of December 31, 2019, was approximately $40.0 million, relating to share grants, which was expected to be recognized over a weighted average period of approximately 2.2 years. The aggregate fair value amount of share grants that vested during 2019 was $20.7 million.

Related Party Transactions

12 Months Ended

Dec. 31, 2019

Related Party Transactions

Note 15 – Related Party Transactions

We conduct business with a related party company, Lite-On Semiconductor Corporation; (“LSC”), and its subsidiaries and affiliates, and Nuvoton Technology Corporation and its subsidiaries and affiliates (collectively, “Nuvoton”). LSC is our largest stockholder, owning approximately 15.2% of our outstanding Common Stock as of December 31, 2019, and is a member of the Lite-On Group of companies. In the third quarter of 2019 we entered into a Share Swap Agreement that provides for the acquisition of LSC and its subsidiaries by the Company. At the effective date of the transaction, each share of LSC will be converted into the right to receive TWD $42.50 per share in cash, or approximately US $1.42 per share based on December 31, 2019 exchange rates. The aggregate consideration to be paid by the Company, based on the December 31, 2019 exchange rate, is approximately $437 million. This amount is subject to change, based on the Taiwan dollar to United States dollar exchange rate at closing. The acquisition received LSC shareholder approval on October 25, 2019, and we anticipate completing the acquisition in the second half of 2020, subject to customary closing conditions and regulatory approvals. We expect to fund the purchase price of the transaction primarily with proceeds from a new bank financing arrangement. We sold products to LSC totaling less than 1% of our net sales for the years ended December 31, 2019, 2018 and 2017, respectively. Raymond Soong, the Chairman of the Board of Directors, is the Chairman of LSC, and is the Chairman of Lite-On Technology Corporation (“LTC”), a significant shareholder of LSC. C.H. Chen, our former President and Chief Executive Officer and currently the Vice Chairman of the Board of Directors, is also Vice Chairman of LSC and a board member of LTC. Dr. Keh-Shew Lu, our President and Chief Executive Officer and a member of our Board of Directors, is a board member of LTC, and a board member of Nuvoton. We consider our relationships with LSC, a member of the Lite-On Group of companies, and Nuvoton to be mutually beneficial and we plan to continue our strategic alliance with LSC and Nuvoton. We purchase wafers from Nuvoton for use in our production process.

We also conduct business with Keylink International (B.V.I.) Inc. and its subsidiaries and affiliates (“Keylink”). Keylink is our 5% partner in our Shanghai assembly and test facilities. We sell products to, and purchase inventory from, companies owned by Keylink. We sold products to companies owned by Keylink, totaling approximately 1% of net sales for each of the years ended December 31, 2019, 2018 and 2017. In addition, our subsidiaries in China lease their manufacturing facilities in Shanghai from, and subcontract a portion of our manufacturing process (metal plating and environmental services) to, Keylink. We also pay a consulting fee to Keylink. The aggregate amounts paid to Keylink for the years ended December 31, 2019, 2018 and 2017 were approximately $15.3 million, $16.6 million and $17.1 million, respectively. In addition, Chengdu Ya Guang Electronic Company Limited (“Ya Guang”) is our 2% partner in one of our Chengdu assembly and test facilities and our 5% partner in our other Chengdu assembly and test facilities; however, we have no material transactions with Ya Guang, other than this joint venture. We also purchase materials from Jiyuan Crystal Photoelectric Frequency Technology Ltd. (“JCP”) an FCP manufacturing company in which we have made an equity investment and account for using the equity method of accounting.

The Audit Committee of the Board reviews all related party transactions for potential conflict of interest situations on an ongoing basis, all in accordance with such procedures as the Audit Committee may adopt from time to time.

The table below sets forth net sales and purchases from related parties for the twelve months ended December 31:

	2019		2018		2017
LSC, its subsidiaries and affiliates
Net sales	$	912	$	1,179	$	1,406
Purchases	$	13,799	$	21,126	$	24,313
Keylink
Net sales	$	15,543	$	12,227	$	8,856
Purchases	$	2,399	$	3,581	$	3,827
Nuvoton
Purchases	$	7,719	$	11,152	$	11,407
JCP
Purchases	$	625	$	600	$	1,105

The table below sets forth accounts receivable from and accounts payable to related parties at December 31:

	2019		2018
LSC, its subsidiaries and affiliates
Accounts receivable	$	184	$	286
Accounts payable	$	2,154	$	2,696
Keylink
Accounts receivable	$	31,598	$	6,264
Accounts payable	$	28,244	$	4,656
Nuvoton
Accounts payable	$	1,055	$	1,939
JCP
Accounts payable	$	173	$	151

Segment Information, Revenue and Enterprise-Wide Disclosures

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Segment Information, Revenue and Enterprise-Wide Disclosures

Note 16 – Segment Information, Revenue and Enterprise-Wide Disclosures

Segment Reporting. For financial reporting purposes, we operate in a single segment, standard semiconductor products, through our various manufacturing and distribution facilities. We aggregate our products because the products are similar and have similar economic characteristics, use similar production processes and share the same customer type. Our primary operations include operations in Asia, North America and Europe. The accounting policies of the operating entities are the same as those described in the summary of significant accounting policies.

The tables below set forth net sales based on the location of the subsidiary producing the net sale:

2019	Asia			North America			Europe			Consolidated
Total sales	$	1,234,750		$	612,697		$	234,092		$	2,081,539
Inter-company sales		(418,377	)		(320,746	)		(93,286	)		(832,409	)
Net sales	$	816,373		$	291,951		$	140,806		$	1,249,130

Property, plant and equipment	$	379,075		$	23,104		$	67,395		$	469,574
Assets	$	1,207,331		$	216,250		$	215,803		$	1,639,384

2018	Asia			North America			Europe			Consolidated
Total sales	$	1,069,068		$	179,459		$	195,406		$	1,443,933
Inter-company sales		(150,421	)		(24,322	)		(55,201	)		(229,944	)
Net sales	$	918,647		$	155,137		$	140,205		$	1,213,989

Property, plant and equipment	$	392,445		$	30,507		$	23,883		$	446,835
Assets	$	1,095,037		$	240,540		$	190,794		$	1,526,371

2017	Asia			North America			Europe			Consolidated
Total sales	$	968,720		$	171,964		$	175,004		$	1,315,688
Inter-company sales		(128,924	)		(71,608	)		(60,952	)		(261,484	)
Net sales	$	839,796		$	100,356		$	114,052		$	1,054,204

Property, plant and equipment	$	390,850		$	44,523		$	23,796		$	459,169
Assets	$	1,061,686		$	230,997		$	195,990		$	1,488,673

Disaggregation of Revenue. We disaggregate revenue from contracts with customers into direct sales and distribution sales (“Distributors”) and by geographic area. Direct sales customers consist of those customers using our product in their manufacturing process, and Distributors are those customers who resell our products to third parties. We sell our products to customers in multiple areas of the world including Asia, Europe, and North America. Across these regions, we sell products to end users in a variety of markets such as consumer electronics, computing, communications, industrial and automotive. Further, most of our contracts are fixed-price arrangements, and are short term in nature, ranging from days to several months.

The tables below set forth the amount of net sales by type, direct sales or Distributor and the location of the customer based on the location to where the products were shipped for the twelve months ended December 31, 2019, 2018 and 2017:

	Net Sales by Type for the Twelve Months Ended December 31,
	Direct Sales									Distributor
	2019			2018			2017			2019			2018			2017
China	$	228,822		$	226,360		$	220,390		$	404,977		$	436,265		$	372,737
United States		10,161			15,644			16,522			90,435			104,598			69,755
Korea		22,099			16,562			17,765			38,269			47,398			48,083
Germany		11,559			11,770			10,879			66,496			81,944			63,423
Singapore		568			2,150			873			66,945			66,003			57,697
Taiwan		2,748			2,846			6,327			90,753			73,498			61,042
All others ⁽¹⁾		131,894			71,665			61,699			83,404			57,286			47,012
Total	$	407,851		$	346,997		$	334,455		$	841,279		$	866,992		$	719,749

	Percent of Net Sales by Type for the Twelve Months Ended December 31,
	Direct Sales									Distributor
	2019			2018			2017			2019			2018			2017
China		56	%		65	%		66	%		48	%		50	%		52	%
United States		2	%		5	%		5	%		11	%		12	%		10	%
Korea		5	%		5	%		5	%		5	%		5	%		7	%
Germany		3	%		3	%		3	%		8	%		9	%		9	%
Singapore		-			1	%		-			8	%		8	%		8	%
Taiwan		1	%		1	%		2	%		11	%		8	%		8	%
All others ⁽¹⁾		33	%		20	%		19	%		9	%		8	%		6	%
Total		100	%		100	%		100	%		100	%		100	%		100	%

	Total Net Sales for the Twelve Months Ended December 31,
	Dollar									Percent of Net Sales
	2019			2018			2017			2019			2018			2017
China	$	633,799		$	662,625		$	593,127			51	%		55	%		56	%
United States		100,596			120,242			86,277			8	%		10	%		8	%
Korea		60,368			63,960			65,848			5	%		5	%		6	%
Germany		78,055			93,714			74,302			6	%		8	%		7	%
Singapore		67,513			68,153			58,570			5	%		6	%		6	%
Taiwan		93,501			76,344			67,369			7	%		6	%		6	%
All others ⁽¹⁾		215,298			128,951			108,711			18	%		10	%		11	%
Total	$	1,249,130		$	1,213,989		$	1,054,204			100	%		100	%		100	%

(1) Represents countries with less than 3% of the total net sales of each.

The tables below set forth a summary of the above data:

	2019		2018		2017
Direct Sales
Asia	$	316,962	$	292,459	$	285,610
Americas		27,443		26,296		23,696
Europe		63,446		28,242		25,149
Total		407,851		346,997		334,455

Distributor Sales
Asia		625,615		651,659		563,661
Americas		98,095		105,458		69,755
Europe		117,569		109,875		86,333
Total		841,279		866,992		719,749

Total Sales
Asia		942,577		944,118		849,271
Americas		125,538		131,754		93,451
Europe		181,015		138,117		111,482
Total	$	1,249,130	$	1,213,989	$	1,054,204

Major customers – During the twelve months ended December 31, 2019, 2018 and 2017, one customer, a broad-based global distributor that sells to thousands of different end users, accounted for approximately 10.0% or $119.6 million, $120.0 million and $101.7 million, respectively, of our revenue. No customer accounted for 10% or greater of our outstanding accounts receivable at December 31, 2019 or 2018.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 17 – Commitments and Contingencies

Lease commitments – We lease offices, manufacturing plants, equipment, vehicles and warehouses under various lease agreements expiring through 2028. For information related to our lease commitments see Note 9.

In addition, we have the following land right leases. None of the leases requires a rental payment.

Location	Term (years)	Expiration Date
Chengdu, China	50	2061
Shanghai, China^*	50	2056
Shandong, China	50	2058
Shanghai, China^*	50	2058
Yangzhou, China	50	2065

*Separate leases by separate Diodes’ subsidiaries

Purchase commitments – We have entered into non-cancelable purchase contracts for capital expenditures, primarily for manufacturing equipment, for approximately $30.0 million at December 31, 2019. In addition to these purchase commitments, we have equity investment obligations for our Chengdu facilities of $25 million for 2020, and capital investment obligations of $25 million and $16 million for 2020 and 2021, respectively. As of December 31, 2019, we also had a commitment to purchase approximately $63.6 million of wafers to be used in our manufacturing process. These wafer purchases will occur during 2020.

Contingencies - From time to time, we are involved in various legal proceedings that arise in the normal course of business. While we intend to defend any lawsuit vigorously, we presently believe that the ultimate outcome of any current pending legal proceeding will not have any material adverse effect on our financial position, cash flows or operating results. However, litigation is subject to inherent uncertainties, and unfavorable rulings could occur. An unfavorable ruling could include monetary damages, which could impact on our business and operating results for the period in which the ruling occurs or future periods. Based on information available, we evaluate the likelihood of potential outcomes. We record the appropriate liability when the amount is deemed probable and reasonably estimable. In addition, we do not accrue for estimated legal fees and other directly related costs as they are expensed as incurred. The Company is not currently a party to any pending litigation that the Company considers material.

Derivative Financial Instruments

12 Months Ended

Dec. 31, 2019

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

Note 18 – Derivative Financial Instruments

In accordance with ASC 815 we recognize derivative instruments on our balance sheet, and we measure them at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether we have elected to designate the derivative as being in a hedging relationship, and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivative instruments that are designated, and qualify as hedges of the exposure to changes in the fair value are considered fair value hedges. Derivative instruments that are designated, and qualify as hedges of the exposure to variability in expected future cash flows are considered cash flow hedges. Derivative instruments may also be designated as hedges of the foreign currency exposure of a net investment in a foreign operation. We currently only utilize cash flow hedges and do not use derivatives for trading or speculative purposes.

Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge, or the earnings effect of the hedged forecasted transactions in a cash flow hedge. We may enter into derivative contracts that are intended to economically hedge certain risks, even though we elect not to apply hedge accounting under ASC 815. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in the consolidated statements of income. Specific information about the valuations of derivatives is described in Note 1 and classification of derivatives in the fair value hierarchy is described in Note 3. Currently our interest rate swaps and interest rate collars are designated as hedges while our foreign exchange contracts are not designated as hedges.

The effective portion of changes in the fair value of derivatives designated and qualifying as cash flow hedges is recorded in accumulated other comprehensive loss and is subsequently reclassified into earnings in the period in which the hedged forecasted transaction affects earnings.

Certain of the Company's agreements with its derivative counterparties contain provisions where if certain merger activity, a change of control, or a capital structure change occurs that materially changes the Company's creditworthiness in an adverse manner, the Company’s counterparty may have the right to terminate any derivative transactions under such agreement.

The company has agreements with each of its derivative counterparties that contain a provision where the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company's default on the indebtedness.

Hedges of Foreign Currency Risk

We are exposed to fluctuations in various foreign currencies against our different functional currencies. We use foreign currency forward agreements to manage this exposure. At December 31, 2019 and 2018, we had outstanding foreign currency forward contracts that are intended to preserve the economic value of foreign currency denominated monetary assets and liabilities; these instruments are not designated for hedge accounting treatment in accordance with ASC 815. There is no fair value of our foreign exchange hedges; therefore they are not recorded in our Consolidated Balance Sheets. As of December 31, 2019 and 2018, the total notional amounts of these foreign exchange contracts was $106.0 million and $122.4 million, respectively.

The tables below set forth outstanding foreign currency forward contracts at December 31, 2019 and 2018:

Notional Amount

Effective Date

Maturity Date

Index*

Weighted Average Strike Rate

Cash Flow Hedge Designation

1,844

December 2019

February 2020

EUR/GPB

0.8471

Non-designated

3,375

December 2019

February 2020

EUR/USD

1.123

Non-designated

25,957

December 2019

February 2020

GPB/USD

1.3257

Non-designated

39,340

December 2019

February 2020

USD/CNY

6.9762

Non-designated

763

December 2019

February 2020

USD/JPY

108.732

Non-designated

33,621

December 2019

February 2020

USD/TWD

29.988

Non-designated

500

January 2019

January 2020

USD/TWD

30.635

Non-designated

500

October 2019

February 2020

USD/TWD

30.571

Non-designated

1,221

December 2018

February 2019

EUR/GPB

0.8981

Non-designated

12,538

December 2018

February 2019

EUR/USD

1.1479

Non-designated

8,463

December 2018

February 2019

GPB/USD

1.2785

Non-designated

44,946

December 2018

February 2019

USD/CNY

6.8738

Non-designated

844

December 2018

February 2019

USD/JPY

110.14

Non-designated

54,041

December 2018

February 2019

USD/TWD

30.559

Non-designated

300

December 2018

January 2019

USD/TWD

30.669

Non-designated

* EUR = Euro

GBP = British Pound Sterling

USD = United States Dollar

CNY = Chinese Yuan Renminbi

JPY = Japan Yen

TWD = Taiwan dollar

Hedges of Interest Rate Risk

The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps, including interest rate collars, as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount.

The table below sets forth information related to the number of and the notional amount of our interest rate related derivative instruments at December 31 2019 and December 31, 2018:

	Number of Instruments		Notional Amount
	2019	2018	2019		2018
Interest rate swaps and collars	9	12	$	200,000	$	210,000

The table below sets forth the fair value of the Company’s interest rate related derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2019 and December 31, 2018:

	Fair Value
	Other Current Assets				Other Assets				Other Current Liabilities				Other Liabilities
	2019		2018		2019		2018		2019		2018		2019		2018
Interest rate swaps and collars	$	194	$	1,936	$	36	$	2,795	$	51	$	-	$	127	$	-

The tables below sets forth the effect of the Company’s derivative financial instruments on the Consolidated Statements of Income for the years ended December 31 2019, 2018 and 2017:

	Amount of Gain or (Loss) Recognized in OCI on Derivative							Location of Gain or (Loss) Reclassified from Accumulated OCI into Income							Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion Excluded from Effectiveness Testing)	Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Derivative Instruments Designated as Hedging Instruments									Amount of Gain or (Loss) Reclassified from Accumulated OCI into Net Income

	December 31,								December 31,							December 31,
	2019			2018		2017			2019		2018		2017			2019		2018		2017
Interest rate swaps and collars	$	(2,997	)	$	1,790	$	1,567	Interest expense	$	1,248	$	860	$	577	N/A	$	-	$	-	$	-
Cross currency swaps		(298	)		-		-	N/A		-		-		-	Interest income		688		-

We estimate that $0.3 million of net derivative gains included in accumulated other comprehensive income (“AOCI”) as of December 31, 2019, will be reclassified into earnings within the following 12 months. No gains or losses were reclassified from AOCI into earnings as a result of forecasted transactions that failed to occur during fiscal year 2019.

	Amount of Gain or (Loss) Recognized in Net Income								Location of Gain or (Loss) Recognized in Net Income
Derivatives Not Designated As Hedging Instruments	Amount of Gain or (Loss) Recognized in Net Income
	December 31,
	2019			2018			2017
Foreign currency forward contracts	$	(3,662	)	$	(8,493	)	$	1,491	Foreign currency loss, net

At December 31, 2019 and 2018, the fair value of derivatives in a net asset position, which includes accrued interest but excludes any adjustments for nonperformance risk, related to these agreements was $0.1 million and $4.7 million, respectively. As of December 31, 2019 and 2018, the Company had not posted any collateral related to these agreements.

Restructuring Costs

12 Months Ended

Dec. 31, 2019

Restructuring And Related Activities [Abstract]

Restructuring Costs

Note 19 – Restructuring Costs

In February 2017, the Company announced its plan to transfer its wafer fabrication operation at KFAB to other Company-owned wafer fabrication plants and external foundries. The Company ceased production operations at KFAB late in third quarter 2017, and vacated and returned the premises to the landlord in November 2017. Employees were provided retention and standard severance packages. During 2018 and 2017, the Company received $3.7 million and $6.5 million, respectively of insurance proceeds as a result of the fires sustained at the KFAB facility during 2016. The $3.7 million received in 2018 and $2.0 million received in 2017 were recorded in Other Income. The remaining $4.5 million received in 2017 was recorded in Cost of Goods Sold. There are outstanding insurance claims. Also during 2017, the Company recorded $1.9 million of asset impairment related to the shut-down of KFAB.

The table below sets forth the restructuring costs, recorded in restructuring expense in the Condensed Consolidated Statements of Operations, incurred during the twelve months ended December 31, 2018 and 2017:

	Twelve Months Ended December 31,
	2018			2017
Early supply contract termination	$	-		$	1,985
Cost of equipment relocation, shutdown cost and other		220			3,591
Asset retirement obligation		-			1,403
Retention costs		(14	)		3,158
	$	206		$	10,137

The table below sets forth the costs accrued related to the KFAB restructuring:

							Equipment
							Relocation,
	Early Contract						Shutdown
	Termination			Retention Costs			Cost and Other			Total
Beginning balance, January 1, 2017	$	-		$	-		$	-		$	-
Costs accrued		1,985			3,158			3,591			8,734
Restructuring costs paid		(1,985	)		(2,499	)		(2,946	)		(7,430	)
Balance at December 31, 2017		-			659			645			1,304
Costs accrued		-			(14	)		526			512
Restructuring costs paid		-			(645	)		(1,171	)		(1,816	)
Balance at December 31, 2018	$	-		$	-		$	-		$	-

Based on continued negotiations with the landlord, we recorded an additional $1.4 million of asset retirement obligations related the KFAB restructuring. This asset retirement obligation is for the estimated amounts to be paid to contractors to remediate the KFAB facility upon vacating the property. The table below sets forth the asset retirement obligation related to the KFAB restructuring:

Asset retirement obligation, January 1, 2017	$	486
Accrual of additional asset retirement obligation		1,403
Amount paid		(1,500	)
Asset retirement obligation, December 31, 2017		389
Accrual of additional asset retirement obligation		-
Amount paid		(389	)
Asset retirement obligation, December 31, 2018	$	-

In connection with the asset retirement obligation, as of December 31, 2018, the offsetting asset has been fully amortized.

Business Acquisitions

12 Months Ended

Dec. 31, 2019

Business Combinations [Abstract]

Business Acquisitions

Note 20 – Business Acquisitions

Wafer Fabrication Facility Acquisition

On April 1, 2019, the Company completed the previously announced acquisition of GFAB. The Company recorded the purchase of GFAB as a business acquisition. The Company purchased GFAB in order to increase the Company’s wafer production capacity. Total consideration paid by the Company was $33.2 million and was funded by advances under the revolving portion of our long-term credit facility. The facility and assets were wholly acquired, and there is no remaining minority interest. The goodwill will not be tax deductible. The Company also incurred acquisition costs of approximately $0.6 million that were recognized in selling, general and administrative expense. Due to a lack of data we are unable to provide historical financial pro forma data. The table below sets forth the fair value of the assets and liabilities recorded in the GFAB acquisition and the corresponding line item in which the item is recorded in our condensed consolidated balance sheet.

Property, plant and equipment	$	24.4
Inventories		3.6
Prepaid expenses and other		5.2
Goodwill		0.9
Deferred tax liabilities		1.0

LSC Acquisition

In the third quarter of 2019 we entered into a Share Swap Agreement that provides for the acquisition of LSC and its subsidiaries by the Company. At the effective date of the transaction, each share of LSC will be converted into the right to receive TWD $42.50 per share in cash, or approximately US $1.42 per share based on December 31, 2019 exchange rates. The aggregate consideration to be paid by the Company, based on the December 31, 2019 exchange rate, is approximately $437 million. This amount is subject to change, based on the Taiwan dollar to United States dollar exchange rate at closing. The acquisition received LSC shareholder approval on October 25, 2019, and we anticipate completing the acquisition in the second half of 2020, subject to customary closing conditions and regulatory approvals. We expect to fund the purchase price of the transaction primarily with proceeds from a new bank financing arrangement.

Eris Technology Acquisitions

In July 2018, our 51% owned subsidiary, ERIS Technology Corporation (“Eris”), acquired from Yea Shin Technology Corporation ("Yea Shin") and its shareholders 51% of Yea Shin’s outstanding shares for approximately $6.4 million in cash. Yea Shin operates a wafer fabrication facility located in Tao Yuan county, Taiwan that was established in 1993. The purpose of the acquisition is to expand the current wafer production capacity of Eris.

Eris also entered into a property purchase agreement with Yong Xiang Development Corporation (“Yong Xiang”) to purchase the plant and facility leased by it to Yea Shin. The total purchase price of the property is approximately $25.5 million. Eris completed the purchase of the facility in June 2019.

Eris has leased from Yong Xiang the plant and facility until the purchase has been completed. The monthly lease payment is approximately $0.04 million for the first 8.5 months and approximately $0.03 million for the remaining period. .

Selected Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2019

Selected Quarterly Financial Information [Abstract]

Selected Quarterly Financial Data

Note 21 – Selected Quarterly Financial Data (Unaudited)

	1st Quarter		2nd Quarter		3rd Quarter		4th Quarter
2019
Net sales	$	302,293	$	322,006	$	323,674	$	301,157
Gross profit		112,411		121,988		122,046		109,362
Net income attributable to common shareholders		31,716		36,284		38,060		47,190
Earnings per share attributable to common shareholders
Basic	$	0.63	$	0.72	$	0.75	$	0.92
Diluted	$	0.62	$	0.70	$	0.73	$	0.90

	1st Quarter		2nd Quarter		3rd Quarter		4th Quarter
2018
Net sales	$	274,512	$	304,085	$	320,946	$	314,446
Gross profit		98,595		107,268		115,214		114,199
Net income (loss) attributable to common shareholders		18,526		25,068		30,908		29,519
Earnings (loss) per share attributable to common shareholders
Basic	$	0.38	$	0.50	$	0.62	$	0.59
Diluted	$	0.37	$	0.49	$	0.61	$	0.58

Note: The sum of the quarterly earnings per share may not equal the full year amount, as the computations of the weighted average number of common shares outstanding for each quarter and for the full year are performed independently.

Summary of Operations and Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Nature of Operations

Nature of operations

Principles of consolidation

Use of estimates

Revenue recognition

Product warranty

Product warranty – We generally warrant our products for a period of one year from the date of sale. Historically, warranty expense has not been material.

Cash, cash equivalents, and short-term investments

Allowance for doubtful accounts

Inventories

Property, plant and equipment

Goodwill and other indefinite lived intangible assets

Impairment of long-lived assets

Business combinations

Income taxes

Research and development costs

Shipping And Handling Costs

Concentration of credit risk

Valuation of financial instruments

Share-based compensation

Treasury stock

Functional currencies and foreign currency translation

Defined benefit plan

Noncontrolling interest

Contingencies

Comprehensive income (loss)

As of December 31, the accumulated balance for each component of comprehensive income is as follows:

	2019			2018
Unrealized foreign currency losses	$	(63,053	)	$	(64,553	)
Unrealized gain on interest rate swap, net of tax	$	(391	)	$	3,261
Unrealized loss on defined benefit plan	$	(44,695	)	$	(40,554	)

Reclassifications

Reclassifications – Certain immaterial amounts from prior periods have been reclassified to conform to the current years’ presentation.

Recently Issued Accounting Pronouncements

The Financial Accounting Standards Board (“FASB”) issued the following Accounting Standards Updates (“ASU”) which could have potential impact to the Company’s financial statements:

Recently Adopted Standards

•

Not record leases with an initial term of 12 months or less on the balance sheet;

•

Not separate non-lease components of leases from the lease components; and

•

Not reassess (1) the definition of a lease, (2) lease classification, and (3) initial direct costs for existing leases during transition.

Standards Effective in Future Years

The FASB has issued the following relevant standards, effective in future years, which are not expected to have a material impact on our consolidated condensed financial statements:

Standard No.	Standard Name	Standard Effective Date
2018-13	Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement	January 1, 2020
2018-14	Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans	January 1, 2020

Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

	Twelve Months Ended December 31,
	2019		2018		2017
Earnings (numerator)
Net income (loss) attributable to common stockholders	$	153,250	$	104,021	$	(1,805	)

Shares (denominator)
Weighted average common shares outstanding (basic)		50,787		49,841		48,824
Dilutive effect of stock options and stock awards outstanding		1,073		1,094		-
Adjusted weighted average common shares outstanding (diluted)		51,860		50,935		48,824

Earnings (loss) per share attributable to common stockholders
Basic	$	3.02	$	2.09	$	(0.04	)
Diluted	$	2.96	$	2.04	$	(0.04	)

Stock options and stock awards excluded from EPS calculation because their inclusion would be anti-dilutive (In thousands)		101		1,103		3,508

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Financial Assets At Fair Value

Financial assets and liabilities carried at fair value as of December 31, 2019, are classified in the following table:

Description	Fair Market Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Changes in Fair Values Included in Current Period Earnings
Short-term investments	$	4,825	$	4,825	$	-	$	-	$	-
Interest rate swaps and collars		51		-		51		-		-
Deferred compensation investments		12,912		2,534		10,378		-		-

Financial assets and liabilities carried at fair value as of December 31, 2018 are classified in the following table:

Description	Fair Market Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Changes in Fair Values Included in Current Period Earnings
Short-term investments	$	7,499	$	5,594	$	1,905	$	-	$	-
Interest rate swap assets		4,731		-		4,731		-		-
Deferred compensation investments		10,104		3,377		6,727		-		-

Inventories (Tables)

12 Months Ended

Dec. 31, 2019

Inventory Disclosure [Abstract]

Schedule of Inventory Current

Inventories, stated at the lower of cost or market value, at December 31 were:

	2019		2018
Finished goods	$	62,900	$	59,244
Work-in-progress		55,082		59,166
Raw materials		118,490		97,025
	$	236,472	$	215,435

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment [Abstract]

Schedule of Property Plant and Equipment

Property, plant and equipment at December 31 were:

	2019			2018
Buildings and leasehold improvements	$	228,522		$	208,184
Machinery and equipment		863,771			817,202
		1,092,293			1,025,386
Less: Accumulated depreciation and amortization		(706,658	)		(635,969	)
		385,635			389,417
Construction in-progress		30,747			16,886
Land		53,192			40,532
	$	469,574		$	446,835

Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2019

Intangible Assets Net Excluding Goodwill [Abstract]

Schedule of Intangible Assets

Intangible assets subject to amortization at December 31 were as follows:

December 31, 2019
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	12,931	$	(10,634	)	$	(254	)	$	2,043
Developed product technology	2-10 years		159,129		(77,915	)		(7,857	)		73,357
Customer relationships	7-12 years		62,093		(30,138	)		(1,682	)		30,273
Software license and other	3-4 years		5,822		(5,765	)		(49	)		8
Total amortized intangible assets			239,975		(124,452	)		(9,842	)		105,681
Intangible assets with indefinite lives
In process research and development	Indefinite		4,580		-			-			4,580
Trademarks and trade names	Indefinite		10,303		-			(1,041	)		9,262
Total Intangible assets with indefinite lives			14,883		-			(1,041	)		13,842
Total intangible assets		$	254,858	$	(124,452	)	$	(10,883	)	$	119,523

December 31, 2018
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	11,823	$	(9,848	)	$	(307	)	$	1,668
Developed product technology	2-10 years		159,129		(66,112	)		(6,221	)		86,796
Customer relationships	7-12 years		62,093		(24,737	)		(1,689	)		35,667
Software license and other	3-4 years		5,822		(5,713	)		(64	)		45
Total amortized intangible assets			238,867		(106,410	)		(8,281	)		124,176
Intangible assets with indefinite lives
In process research and development	Indefinite		4,580		-			-			4,580
Trademarks and trade names	Indefinite		10,303		-			(1,124	)		9,179
Total Intangible assets with indefinite lives			14,883		-			(1,124	)		13,759
Total intangible assets		$	253,750	$	(106,410	)	$	(9,405	)	$	137,935

Schedule of Expected Amortization Expense

The schedule below sets future amortization expense of our currently owned intangible assets:

2020	$	15,671
2021		15,065
2022		14,451
2023		14,186
2024		13,831
2025 and thereafter		32,477
Total	$	105,681

Goodwill (Tables)

12 Months Ended

Dec. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Changes in Goodwill

Changes in goodwill for the years ended December 31, were as follows:

Balance at December 31, 2017	$	134,187
Acquisitions:
ERIS acquisition of Yea Shin Technology Corporation		1,029
Foreign currency translation adjustment		(2,779	)
Balance at December 31, 2018	$	132,437
Acquisitions:
Wafer fabrication in Greenock, Scotland		931
Canyon Investment		1,671
ERIS acquisition of Yea Shin Technology Corporation		4,320
Foreign currency translation adjustment		1,959
Balance at December 31, 2019	$	141,318

Bank Credit Agreements and Other Short-Term and Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2019

Long Term Debt By Current And Noncurrent [Abstract]

Schedule of Debt

Long-term debt balances as of December 31, consist of the following:

	2019			2018
Notes payable to Bank of Taiwan, original principal amount of TWD 140 million, fixed interest rate of 1.3%, matures June 28, 2033.	$	4,242		$	4,442
Notes payable to Yuan Ta Bank, original principal amount of TWD 113 million, fixed interest rate of 1.7%, matured on January 29, 2019.		-			749
Notes payable to China Trust Bank, original principal of TWD 576 million, fixed interest rate of 1.7%, matures May 27, 2024		19,212

Term loan and revolver		75,187			210,000
Total long-term debt		98,641			215,191
Less: Current portion		(33,105	)		(27,613	)
Less: Unamortized debt issuance costs		(1,135	)		(1,435	)
Long-term debt, net of current portion	$	64,401		$	186,143

Schedule of Maturities of Long Term Debt

The table below sets forth the annual contractual maturities of long-term debt at December 31, 2019:

2020	$	33,102
2021		43,620
2022		4,903
2023		1,571
2024		12,689
2025 and thereafter		2,756
Total long-term debt	$	98,641

Leases (Tables)

12 Months Ended

Dec. 31, 2019

Leases [Abstract]

Components of Lease Expense

The components of lease expense are set forth in the table below:

	Twelve Months Ended
	December 31, 2019
Operating lease expense	$	14,824
Finance lease expense:
Amortization of assets		978
Interest on lease liabilities		48
Short-term lease expense		336
Variable lease expense		2,663
Total lease expense	$	18,849

Supplemental Balance Sheet Information Related to Leases

The table below sets forth supplemental balance sheet information related to leases:

	December 31, 2019
Operating leases:
Operating lease ROU assets	$	57,427

Current operating lease liabilities		12,554
Noncurrent operating lease liabilities		27,545
Total operating lease liabilities	$	40,099

Finance leases:
Finance lease ROU assets	$	3,396
Accumulated amortization		(1,924	)
Finance lease ROU assets, net	$	1,472

Current finance lease liabilities	$	903
Non-current finance lease liabilities		138
Total finance lease liabilities	$	1,041

Weighted average remaining lease term (in years):
Operating leases		4.4
Finance leases		1.3

Weighted average discount rate:
Operating leases		3.8	%
Finance leases		3.0	%

Supplemental Cash Flow and Other Information Related to Leases

The table below sets forth supplemental cash flow and other information related to leases:

	Twelve Months Ended
	December 31, 2019
Cash paid for the amounts included in the measurements of lease liabilities:
Operating cash outflows from operating leases	$	18,325
Operating cash outflows from finance leases		48
Financing cash outflow from finance leases		1,082

ROU assets obtained in exchange for lease liabilities incurred:
Operating leases		3,956

Schedule of Operating and Finance Lease Liability Maturities

The table below sets forth information about lease liability maturities:

	December 31, 2019
	Operating Leases			Finance Leases
2020	$	13,779		$	922
2021		9,766			138
2022		8,276			-
2023		4,537			-
2024		2,433			-
2025		2,328			-
2026 and thereafter		2,573			-
Total lease payments		43,692			1,060
Less: imputed interest		(3,593	)		(19	)
Total lease obligations		40,099			1,041
Less: current obligations		(12,554	)		(903	)
Long-term lease obligations	$	27,545		$	138

Accrued Liabilities and Other Long-Term Liabilities (Tables)

12 Months Ended

Dec. 31, 2019

Accrued Liabilities Current And Noncurrent [Abstract]

Schedule of Accrued Liabilities

Accrued liabilities and other current liabilities at December 31 were:

	2019		2018
Accrued expenses	$	33,733	$	28,170
Compensation and payroll taxes		34,043		33,632
Equipment purchases		10,167		12,568
Operating lease		12,554		-
Finance lease		903		-
Accrued pricing adjustments		5,617		3,591
Accrued professional services		3,258		3,242
Other		296		1,402
	$	100,571	$	82,605

Schedule of Other Long-Term Liabilities

Other long-term liabilities at December 31 were:

	2019		2018
Accrued defined benefit plan	$	28,795	$	26,349
Unrecognized tax benefits		28,215		27,711
Operating lease		27,545		-
Finance lease		138		-
Deferred grans and subsidy		12,774		15,359
Deferred compensation		12,166		9,091
Tax contingencies		8,631		8,475
Other		2,281		3,794
	$	120,545	$	90,779

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax Expense (Benefit)

The table below sets forth our (loss) income before taxes for the years ended December 31:

Income (loss) before income taxes	2019		2018			2017
U.S.	$	73,352	$	(24,141	)	$	(72,668	)
Foreign		124,894		174,103			135,259
Total	$	198,246	$	149,962		$	62,591

The table below sets forth the components of our income tax provision (benefit) for the years ended December 31:

	2019		2018			2017
Current tax provision
Federal	$	259	$	-		$	-
Foreign		28,829		42,726			31,820
State		92		24			7
		29,180		42,750			31,827
Deferred tax provision (benefit)
Federal		886		2,400			30,186
Foreign		11,994		(3,107	)		(2,352	)
State		30		56			(8	)
		12,910		(651	)		27,826

Liability for unrecognized tax benefits		2,041		2,457			2,672
Total income tax provision	$	44,131	$	44,556		$	62,325

Schedule of Effective Income Tax Rate Reconciliation

The table below sets forth a reconciliation between the effective tax rate and the statutory tax rates for the years ended December 31:

	2019						2018						2017
				Percent						Percent						Percent
				of pretax						of pretax						of pretax
	Amount			earnings*			Amount			earnings*			Amount			earnings*
Federal tax	$	41,632			21.0		$	31,488			21.0		$	21,907			35.0
State income taxes, net of federal tax provision		1,389			0.7			(375	)		(0.3	)		(15	)		-
Foreign income taxed at lower tax rates		(5,786	)		(2.9	)		(2,844	)		(1.9	)		(23,515	)		(37.6	)
U.S. tax impact of foreign operations		(3,340	)		(1.7	)		4,140			2.8			6,726			10.7
Foreign withholding taxes		22,685			11.4			10,962			7.3			4,343			6.9
Research and development		(3,686	)		(1.9	)		(3,541	)		(2.4	)		(2,643	)		(4.2	)
Liability for unrecognized tax benefits		2,041			1.0			2,457			1.6			2,672			4.3
Valuation allowance		(10,563	)		(5.3	)		(379	)		(0.3	)		2,077			3.3
Employee stock-based compensation		(52	)		(0.0	)		(2,154	)		(1.4	)		1,537			2.5
U.S. Tax Cuts and Jobs Act		-			-			2,762			1.8			45,908			73.4
Other		(189	)		(0.1	)		2,040			1.4			3,328			5.3
Income tax provision	$	44,131			22.3		$	44,556			29.7		$	62,325			99.6

*	The sum of the amounts in the table may not equal to the effective tax rate due to rounding.

Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible

	2019			2018			2017
Balance at January 1,	$	32,209		$	30,581		$	28,849
Additions based on tax positions related to the current year		9,274			4,667			3,492
Additions for prior year tax positions		39			-			863
Reductions for prior year tax positions		(5,870	)		(3,039	)		(2,623	)
Balance at December 31,	$	35,652		$	32,209		$	30,581

Schedule of Deferred Tax Assets and Liabilities

The table below sets forth our deferred tax assets and liabilities as of December 31:

	2019			2018
Deferred tax assets
Inventory cost	$	10,423		$	7,974
Accrued expenses and accounts receivable		4,420			1,866
Foreign tax credits		5,848			17,600
Research and development tax credits		16,263			15,456
Net operating loss carryforwards		24,139			9,635
Lease obligations		3,773			-
Accrued pension		4,629			4,294
Share based compensation and others		7,805			9,972
		77,300			66,797
Valuation allowances		(29,414	)		(25,941	)
Total deferred tax assets, non-current		47,886			40,856
Deferred tax liabilities
Plant, equipment and intangible assets		(13,816	)		(16,661	)
Right of use assets		(4,008	)		-
Outside basis differences and others		(23,648	)		(7,267	)
Total deferred tax liabilities, non-current		(41,472	)		(23,928	)
Net deferred tax assets	$	6,414		$	16,928

Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2019

Compensation And Retirement Disclosure [Abstract]

Schedule of Net Benefit Costs

The table below sets forth net periodic benefit costs of the plan for the twelve months ended December 31:

	Defined Benefit Plan
	2019			2018
Components of net periodic benefit cost:
Service cost	$	256		$	267
Interest cost		4,069			4,151
Recognized actuarial loss		1,546			2,625
Expected return on plan assets		(7,511	)		(7,339	)
Prior service cost		55			-
Net periodic benefit cost	$	(1,585	)	$	(296	)

Schedule of Benefit Obligation, Fair Value of Plan Assets, and Funded Status of our Plan

The table below sets forth the benefit obligation, the fair value of plan assets, and the funded status as of December 31:

	Defined Benefit Plan
	2019			2018
Change in benefit obligation:
Beginning balance	$	141,104		$	166,063
Service cost		255			267
Interest cost		4,045			4,151
Actuarial loss (gain)		11,214			(9,827	)
Benefits paid		(4,158	)		(3,625	)
Settlements		-			(7,471	)
Currency changes		6,220			(8,454	)
Benefit obligation at December 31	$	158,680		$	141,104

Change in plan assets:
Beginning balance - fair value	$	117,162		$	134,234
Employer contribution		2,629			2,796
Actual return on plan assets		11,791			(2,084	)
Benefits paid		(4,158	)		(3,625	)
Settlements		-			(6,731	)
Currency changes		5,197			(7,428	)
Fair value of plan assets at December 31	$	132,621		$	117,162
Underfunded status at December 31	$	(26,059	)	$	(23,942	)

Schedule of Assumptions Used

The following weighted-average assumptions were used to determine net periodic benefit costs for the twelve months ended December 31:

	2019			2018
Discount rate		2.9	%		2.6	%
Expected long-term return on plan assets		6.4	%		5.6	%

The following weighted-average assumption was used to determine the benefit obligations at December 31:

	2019				2018
Discount rate		2.0	%			2.9	%

Schedule of Allocation Of Plan Assets

The table below sets forth the plan asset allocations of the assets in the plan and expected long-term return by asset category

Asset category	Expected long-term return			Asset allocation
Growth assets		7.8	%		70	%
Hedging assets		1.3	%		27	%
Cash		0.8	%		3	%
Total		5.6	%		100	%

Schedule of Expected Benefit Payments

2020	$	4,030
2021		4,592
2022		4,913
2023		5,335
2024		5,668
2025-2029		29,846

Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets

The following table summarizes the major categories of the plan assets:

	December 31, 2019
Asset category	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	14,057	$	-	$	-	$	14,057
Equity securities:
U.K.		-		683		-		683
Overseas equities		-		5,909		-		5,909
Emerging markets		-		11,413		-		11,413
Fixed income securities:
Government bonds		-		5,160		-		5,160
Non-government bonds		-		9,906		-		9,906
Index-linked securities:
U.K. treasury securities		-		166		-		166
Other types of investments
Hedge funds		-		39,710		-		39,710
Property		-		3,224		-		3,224
Liability-driven investments		-		42,014		-		42,014
Other		-		379		-		379
Total	$	14,057	$	118,564	$	-	$	132,621

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Share Based Compensation [Abstract]

Schedule of Share-Based Compensation Expense

The table below sets forth the line items where share-based compensation expense was recorded for the twelve months ended December 31:

	2019		2018		2017
Cost of goods sold	$	925	$	362	$	645
Selling, general and administrative expense		16,687		17,395		15,130
Research and development expense		2,923		2,979		2,834
Total share-based compensation expense	$	20,535	$	20,736	$	18,609

Schedule of Share-Based Compensation Expense by Type

The table below sets forth share-based compensation expense by type for the twelve months ended December 31:

	2019		2018		2017
Stock options	$	-	$	274	$	934
Share grants		20,535		20,462		17,675
Total share-based compensation expense	$	20,535	$	20,736	$	18,609

Schedule of Share Based Compensation Stock Options Activity

The table below sets forth a summary of activity in our stock option plan:

Stock Options	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2016		1,833			23.08
Exercised		(581	)		23.42
Forfeited or expired		(24	)		26.87
Outstanding at December 31, 2017		1,228			22.85
Exercised		(240	)		20.28
Outstanding at December 31, 2018		988			23.47
Exercised		(524	)		22.68			$	10,600
Outstanding and Exercisable at December 31, 2019		464			24.37		2.0	$	14,849

Schedule of Stock Options Outstanding

The table below sets forth information about stock options outstanding at December 31, 2019:

Plan

Range of Exercise Prices

Number Exercisable

Weighted Average Remaining Contractual Life

(Years)

Weighted Average Exercise Price

2001 Plan

$15.05-29.21

259

2.0

23.17

2013 Plan

$23.35-27.92

205

2.0

25.91

Schedule of Nonvested Restricted and Performance Stock Units Activity

The table below sets forth a summary of our non-vested share grants in 2019, 2018 and 2017:

Restricted and Performance Stock Grants	Shares			Weighted Average Grant Date Fair Value ($)		Aggregate Intrinsic Value
Nonvested at December 31, 2016		2,620			21.31
Granted		746			25.23
Vested		(645	)		21.89
Forfeited		(441	)		22.31
Nonvested at December 31, 2017		2,280			22.24
Granted		646			32.06
Vested		(1,213	)		21.39
Forfeited		(46	)		24.72
Nonvested at December 31, 2018		1,667			26.68
Granted		670			38.15
Vested		(573	)		24.90	$	20,682
Forfeited		(67	)		30.44
Nonvested at December 31, 2019		1,697			31.71	$	95,687

Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2019

Schedule of Net Sales and Purchases of Related Party Transactions

The table below sets forth net sales and purchases from related parties for the twelve months ended December 31:

	2019		2018		2017
LSC, its subsidiaries and affiliates
Net sales	$	912	$	1,179	$	1,406
Purchases	$	13,799	$	21,126	$	24,313
Keylink
Net sales	$	15,543	$	12,227	$	8,856
Purchases	$	2,399	$	3,581	$	3,827
Nuvoton
Purchases	$	7,719	$	11,152	$	11,407
JCP
Purchases	$	625	$	600	$	1,105

Schedule of Account Receivable and Payable of Related Party Transactions

The table below sets forth accounts receivable from and accounts payable to related parties at December 31:

	2019		2018
LSC, its subsidiaries and affiliates
Accounts receivable	$	184	$	286
Accounts payable	$	2,154	$	2,696
Keylink
Accounts receivable	$	31,598	$	6,264
Accounts payable	$	28,244	$	4,656
Nuvoton
Accounts payable	$	1,055	$	1,939
JCP
Accounts payable	$	173	$	151

Segment Information, Revenue and Enterprise-Wide Disclosures (Tables)

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Schedule of Net Sales from Based on Location of the Subsidiary

The tables below set forth net sales based on the location of the subsidiary producing the net sale:

2019	Asia			North America			Europe			Consolidated
Total sales	$	1,234,750		$	612,697		$	234,092		$	2,081,539
Inter-company sales		(418,377	)		(320,746	)		(93,286	)		(832,409	)
Net sales	$	816,373		$	291,951		$	140,806		$	1,249,130

Property, plant and equipment	$	379,075		$	23,104		$	67,395		$	469,574
Assets	$	1,207,331		$	216,250		$	215,803		$	1,639,384

2018	Asia			North America			Europe			Consolidated
Total sales	$	1,069,068		$	179,459		$	195,406		$	1,443,933
Inter-company sales		(150,421	)		(24,322	)		(55,201	)		(229,944	)
Net sales	$	918,647		$	155,137		$	140,205		$	1,213,989

Property, plant and equipment	$	392,445		$	30,507		$	23,883		$	446,835
Assets	$	1,095,037		$	240,540		$	190,794		$	1,526,371

2017	Asia			North America			Europe			Consolidated
Total sales	$	968,720		$	171,964		$	175,004		$	1,315,688
Inter-company sales		(128,924	)		(71,608	)		(60,952	)		(261,484	)
Net sales	$	839,796		$	100,356		$	114,052		$	1,054,204

Property, plant and equipment	$	390,850		$	44,523		$	23,796		$	459,169
Assets	$	1,061,686		$	230,997		$	195,990		$	1,488,673

Schedule of Net Sales by Direct Sales or Distributor and Location

	Net Sales by Type for the Twelve Months Ended December 31,
	Direct Sales									Distributor
	2019			2018			2017			2019			2018			2017
China	$	228,822		$	226,360		$	220,390		$	404,977		$	436,265		$	372,737
United States		10,161			15,644			16,522			90,435			104,598			69,755
Korea		22,099			16,562			17,765			38,269			47,398			48,083
Germany		11,559			11,770			10,879			66,496			81,944			63,423
Singapore		568			2,150			873			66,945			66,003			57,697
Taiwan		2,748			2,846			6,327			90,753			73,498			61,042
All others ⁽¹⁾		131,894			71,665			61,699			83,404			57,286			47,012
Total	$	407,851		$	346,997		$	334,455		$	841,279		$	866,992		$	719,749

	Percent of Net Sales by Type for the Twelve Months Ended December 31,
	Direct Sales									Distributor
	2019			2018			2017			2019			2018			2017
China		56	%		65	%		66	%		48	%		50	%		52	%
United States		2	%		5	%		5	%		11	%		12	%		10	%
Korea		5	%		5	%		5	%		5	%		5	%		7	%
Germany		3	%		3	%		3	%		8	%		9	%		9	%
Singapore		-			1	%		-			8	%		8	%		8	%
Taiwan		1	%		1	%		2	%		11	%		8	%		8	%
All others ⁽¹⁾		33	%		20	%		19	%		9	%		8	%		6	%
Total		100	%		100	%		100	%		100	%		100	%		100	%

	Total Net Sales for the Twelve Months Ended December 31,
	Dollar									Percent of Net Sales
	2019			2018			2017			2019			2018			2017
China	$	633,799		$	662,625		$	593,127			51	%		55	%		56	%
United States		100,596			120,242			86,277			8	%		10	%		8	%
Korea		60,368			63,960			65,848			5	%		5	%		6	%
Germany		78,055			93,714			74,302			6	%		8	%		7	%
Singapore		67,513			68,153			58,570			5	%		6	%		6	%
Taiwan		93,501			76,344			67,369			7	%		6	%		6	%
All others ⁽¹⁾		215,298			128,951			108,711			18	%		10	%		11	%
Total	$	1,249,130		$	1,213,989		$	1,054,204			100	%		100	%		100	%

(1) Represents countries with less than 3% of the total net sales of each.

The tables below set forth a summary of the above data:

	2019		2018		2017
Direct Sales
Asia	$	316,962	$	292,459	$	285,610
Americas		27,443		26,296		23,696
Europe		63,446		28,242		25,149
Total		407,851		346,997		334,455

Distributor Sales
Asia		625,615		651,659		563,661
Americas		98,095		105,458		69,755
Europe		117,569		109,875		86,333
Total		841,279		866,992		719,749

Total Sales
Asia		942,577		944,118		849,271
Americas		125,538		131,754		93,451
Europe		181,015		138,117		111,482
Total	$	1,249,130	$	1,213,989	$	1,054,204

Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Summary of Outstanding Foreign Currency Forward Contracts

The tables below set forth outstanding foreign currency forward contracts at December 31, 2019 and 2018:

Notional Amount

Effective Date

Maturity Date

Index*

Weighted Average Strike Rate

Cash Flow Hedge Designation

1,844

December 2019

February 2020

EUR/GPB

0.8471

Non-designated

3,375

December 2019

February 2020

EUR/USD

1.123

Non-designated

25,957

December 2019

February 2020

GPB/USD

1.3257

Non-designated

39,340

December 2019

February 2020

USD/CNY

6.9762

Non-designated

763

December 2019

February 2020

USD/JPY

108.732

Non-designated

33,621

December 2019

February 2020

USD/TWD

29.988

Non-designated

500

January 2019

January 2020

USD/TWD

30.635

Non-designated

500

October 2019

February 2020

USD/TWD

30.571

Non-designated

1,221

December 2018

February 2019

EUR/GPB

0.8981

Non-designated

12,538

December 2018

February 2019

EUR/USD

1.1479

Non-designated

8,463

December 2018

February 2019

GPB/USD

1.2785

Non-designated

44,946

December 2018

February 2019

USD/CNY

6.8738

Non-designated

844

December 2018

February 2019

USD/JPY

110.14

Non-designated

54,041

December 2018

February 2019

USD/TWD

30.559

Non-designated

300

December 2018

January 2019

USD/TWD

30.669

Non-designated

* EUR = Euro

GBP = British Pound Sterling

USD = United States Dollar

CNY = Chinese Yuan Renminbi

JPY = Japan Yen

TWD = Taiwan dollar

Summary of Information Related to Number of and Notional Amount of Interest Rate Related Derivative Instruments

The table below sets forth information related to the number of and the notional amount of our interest rate related derivative instruments at December 31 2019 and December 31, 2018:

	Number of Instruments		Notional Amount
	2019	2018	2019		2018
Interest rate swaps and collars	9	12	$	200,000	$	210,000

Summary of Fair Value of Interest Rate Related Derivative Financial Instruments and Their Classification on Consolidated Balance Sheets

	Fair Value
	Other Current Assets				Other Assets				Other Current Liabilities				Other Liabilities
	2019		2018		2019		2018		2019		2018		2019		2018
Interest rate swaps and collars	$	194	$	1,936	$	36	$	2,795	$	51	$	-	$	127	$	-

Summary of Effect of Derivative Financial Instruments on Consolidated Statements of Income

The tables below sets forth the effect of the Company’s derivative financial instruments on the Consolidated Statements of Income for the years ended December 31 2019, 2018 and 2017:

	Amount of Gain or (Loss) Recognized in OCI on Derivative							Location of Gain or (Loss) Reclassified from Accumulated OCI into Income							Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion Excluded from Effectiveness Testing)	Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Derivative Instruments Designated as Hedging Instruments									Amount of Gain or (Loss) Reclassified from Accumulated OCI into Net Income

	December 31,								December 31,							December 31,
	2019			2018		2017			2019		2018		2017			2019		2018		2017
Interest rate swaps and collars	$	(2,997	)	$	1,790	$	1,567	Interest expense	$	1,248	$	860	$	577	N/A	$	-	$	-	$	-
Cross currency swaps		(298	)		-		-	N/A		-		-		-	Interest income		688		-

	Amount of Gain or (Loss) Recognized in Net Income								Location of Gain or (Loss) Recognized in Net Income
Derivatives Not Designated As Hedging Instruments	Amount of Gain or (Loss) Recognized in Net Income
	December 31,
	2019			2018			2017
Foreign currency forward contracts	$	(3,662	)	$	(8,493	)	$	1,491	Foreign currency loss, net

Restructuring Costs (Tables)

12 Months Ended

Dec. 31, 2019

Restructuring And Related Activities [Abstract]

Schedule of Restructuring Costs, Recorded in Restructuring Expense in Condensed Consolidated Statements of Operations, Incurred

	Twelve Months Ended December 31,
	2018			2017
Early supply contract termination	$	-		$	1,985
Cost of equipment relocation, shutdown cost and other		220			3,591
Asset retirement obligation		-			1,403
Retention costs		(14	)		3,158
	$	206		$	10,137

Schedule of Costs Accrued Related to Restructuring

The table below sets forth the costs accrued related to the KFAB restructuring:

							Equipment
							Relocation,
	Early Contract						Shutdown
	Termination			Retention Costs			Cost and Other			Total
Beginning balance, January 1, 2017	$	-		$	-		$	-		$	-
Costs accrued		1,985			3,158			3,591			8,734
Restructuring costs paid		(1,985	)		(2,499	)		(2,946	)		(7,430	)
Balance at December 31, 2017		-			659			645			1,304
Costs accrued		-			(14	)		526			512
Restructuring costs paid		-			(645	)		(1,171	)		(1,816	)
Balance at December 31, 2018	$	-		$	-		$	-		$	-

Schedule of Asset Retirement Obligation Related to Restructuring

The table below sets forth the asset retirement obligation related to the KFAB restructuring:

Asset retirement obligation, January 1, 2017	$	486
Accrual of additional asset retirement obligation		1,403
Amount paid		(1,500	)
Asset retirement obligation, December 31, 2017		389
Accrual of additional asset retirement obligation		-
Amount paid		(389	)
Asset retirement obligation, December 31, 2018	$	-

Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Selected Quarterly Financial Information [Abstract]

Schedule of Quarterly Financial Data

	1st Quarter		2nd Quarter		3rd Quarter		4th Quarter
2019
Net sales	$	302,293	$	322,006	$	323,674	$	301,157
Gross profit		112,411		121,988		122,046		109,362
Net income attributable to common shareholders		31,716		36,284		38,060		47,190
Earnings per share attributable to common shareholders
Basic	$	0.63	$	0.72	$	0.75	$	0.92
Diluted	$	0.62	$	0.70	$	0.73	$	0.90

	1st Quarter		2nd Quarter		3rd Quarter		4th Quarter
2018
Net sales	$	274,512	$	304,085	$	320,946	$	314,446
Gross profit		98,595		107,268		115,214		114,199
Net income (loss) attributable to common shareholders		18,526		25,068		30,908		29,519
Earnings (loss) per share attributable to common shareholders
Basic	$	0.38	$	0.50	$	0.62	$	0.59
Diluted	$	0.37	$	0.49	$	0.61	$	0.58

Summary of Operations and Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2019 USD ($)
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Product returns and other allowances	$ 163,900,000	$ 158,800,000	$ 158,100,000
Allowance for doubtful accounts	$ 4,900,000	4,100,000
Number of operating segment \| Segment	1
Impairment of goodwill	$ 0	0	0
Cost of goods sold	783,323,000	778,713,000	697,428,000
Foreign exchange transaction losses	3,737,000	3,701,000	7,995,000
Accumulated other comprehensive loss	108,139,000	101,846,000	83,500,000
ROU assets				$ 68,300,000
ROU liabilities				50,400,000
Shipping and Handling
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Cost of goods sold	$ 13,900,000	$ 14,800,000	$ 15,200,000
Land-use Rights \| Other Assets
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
ROU assets				17,100,000
Land-use Rights \| Property, Plant and Equipment
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
ROU assets				$ 2,500,000
Minimum \| Building
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	20 years
Minimum \| Machinery and Equipment
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	3 years
Minimum \| Leaseholds and Leasehold Improvements
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	3 years
Maximum \| Building
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	55 years
Maximum \| Machinery and Equipment
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	10 years
Maximum \| Leaseholds and Leasehold Improvements
Summary of Operations, Significant Accounting Policies, Recently Issued Accounting Pronouncements and Updates to Accounting Policies and Estimates [Line Items]
Estimated useful lives	5 years

Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings (numerator)
Net income (loss) attributable to common stockholders	$ 47,190	$ 38,060	$ 36,284	$ 31,716	$ 29,519	$ 30,908	$ 25,068	$ 18,526	$ 153,250	$ 104,021	$ (1,805)
Shares (denominator)
Weighted average common shares outstanding (basic)									50,787	49,841	48,824
Dilutive effect of stock options and stock awards outstanding									1,073	1,094
Adjusted weighted average common shares outstanding (diluted)									51,860	50,935	48,824
Earnings (loss) per share attributable to common stockholders
Basic	$ 0.92	$ 0.75	$ 0.72	$ 0.63	$ 0.59	$ 0.62	$ 0.50	$ 0.38	$ 3.02	$ 2.09	$ (0.04)
Diluted	$ 0.90	$ 0.73	$ 0.70	$ 0.62	$ 0.58	$ 0.61	$ 0.49	$ 0.37	$ 2.96	$ 2.04	$ (0.04)
Stock options and stock awards excluded from EPS calculation because their inclusion would be anti-dilutive									101	1,103	3,508

Fair Value Measurements - Schedule of Financial Assets At Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 4,825	$ 7,499
Deferred compensation investments	12,912	10,104
Interest Rate Swaps and Collars
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of derivative instruments, asset derivatives	51
Interest Rate Swap Assets
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of derivative instruments, asset derivatives		4,731
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	4,825	5,594
Deferred compensation investments	2,534	3,377
Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		1,905
Deferred compensation investments	10,378	6,727
Significant Other Observable Inputs (Level 2) \| Interest Rate Swaps and Collars
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of derivative instruments, asset derivatives	$ 51
Significant Other Observable Inputs (Level 2) \| Interest Rate Swap Assets
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of derivative instruments, asset derivatives		$ 4,731

Inventories - Schedule of Inventory Current (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished goods	$ 62,900	$ 59,244
Work-in-progress	55,082	59,166
Raw materials	118,490	97,025
Total	$ 236,472	$ 215,435

Property, Plant and Equipment - Schedule of Property Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Abstract]
Buildings and leasehold improvements, Gross	$ 228,522	$ 208,184
Machinery and equipment	863,771	817,202
Property, plant and equipment, at cost	1,092,293	1,025,386
Less: Accumulated depreciation and amortization	(706,658)	(635,969)
Net	385,635	389,417
Construction in-progress	30,747	16,886
Land	53,192	40,532
Property, plant and equipment, net	$ 469,574	$ 446,835	$ 459,169

Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Abstract]
Depreciation		$ 91,543	$ 86,291	$ 76,883
Capital lease obligations			$ 2,100
Gain realized upon selling land	$ 24,300

Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	$ 239,975	$ 238,867
Accumulated Amortization	(124,452)	(106,410)
Currency Exchange	(9,842)	(8,281)
Amortization of Intangible Assets, Net	105,681	124,176
Gross Carrying Amount	14,883	14,883
Currency Exchange	(1,041)	(1,124)
Net	13,842	13,759
Total Intangible Assets - Gross Carrying Amount	254,858	253,750
Total Intangible Assets - Accumulated Amortization	(124,452)	(106,410)
Total Intangible Assets - Currency Exchange and Other	(10,883)	(9,405)
Total Intangible Assets - Net	119,523	137,935
In Process Research and Development
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	4,580	4,580
Net	4,580	4,580
Trademarks and Trade Names
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	10,303	10,303
Currency Exchange	(1,041)	(1,124)
Net	9,262	9,179
Patents
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	12,931	11,823
Accumulated Amortization	(10,634)	(9,848)
Currency Exchange	(254)	(307)
Amortization of Intangible Assets, Net	$ 2,043	$ 1,668
Patents \| Minimum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	5 years	5 years
Patents \| Maximum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	15 years	15 years
Developed Product Technology
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	$ 159,129	$ 159,129
Accumulated Amortization	(77,915)	(66,112)
Currency Exchange	(7,857)	(6,221)
Amortization of Intangible Assets, Net	$ 73,357	$ 86,796
Developed Product Technology \| Minimum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	2 years	2 years
Developed Product Technology \| Maximum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	10 years	10 years
Customer Relationships
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	$ 62,093	$ 62,093
Accumulated Amortization	(30,138)	(24,737)
Currency Exchange	(1,682)	(1,689)
Amortization of Intangible Assets, Net	$ 30,273	$ 35,667
Customer Relationships \| Minimum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	7 years	7 years
Customer Relationships \| Maximum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	12 years	12 years
Software License And Other
Intangible Assets Net Excluding Goodwill [Line Items]
Gross Carrying Amount	$ 5,822	$ 5,822
Accumulated Amortization	(5,765)	(5,713)
Currency Exchange	(49)	(64)
Amortization of Intangible Assets, Net	$ 8	$ 45
Software License And Other \| Minimum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	3 years	3 years
Software License And Other \| Maximum
Intangible Assets Net Excluding Goodwill [Line Items]
Useful life	4 years	4 years

Intangible Assets - Schedule of Expected Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets Future Amortization Expense [Abstract]
2020	$ 15,671
2021	15,065
2022	14,451
2023	14,186
2024	13,831
2025 and thereafter	32,477
Amortization of Intangible Assets, Net	$ 105,681	$ 124,176

Goodwill - Schedule of Changes in Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill
Goodwill beginning balance	$ 132,437	$ 134,187
Foreign currency translation adjustment	1,959	(2,779)
Goodwill ending balance	141,318	132,437
ERIS Acquisition of Yea Shin Technology Corporation
Goodwill
Acquisitions	4,320	$ 1,029
Canyon Investment
Goodwill
Acquisitions	1,671
Wafer Fabrication in Greenock, Scotland
Goodwill
Acquisitions	$ 931

Bank Credit Agreements and Other Short-Term and Long-Term Debt - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jul. 31, 2018
Line Of Credit Facility [Line Items]
Long-term debt	$ 98,641,000	$ 215,191,000
ERIS Technology Corporation
Line Of Credit Facility [Line Items]
Long-term debt	$ 23,500,000
Yea Shin Technology Co Ltd \| ERIS Technology Corporation
Line Of Credit Facility [Line Items]
Percentage of shares acquired by subsidiary in acquiree	51.00%		51.00%
First Loan \| ERIS Technology Corporation
Line Of Credit Facility [Line Items]
Long-term debt	$ 4,300,000
Long term debt maturity year	2033
Second Loan \| ERIS Technology Corporation
Line Of Credit Facility [Line Items]
Long-term debt	$ 19,200,000
Long term debt maturity year	2024
U.S. Credit Facility
Line Of Credit Facility [Line Items]
Lines of credit maximum borrowing capacity	$ 250,000,000
Long-term debt	$ 75,200,000
Line of credit facility, maturity date	Oct. 26, 2021
U.S. Credit Facility \| Maximum
Line Of Credit Facility [Line Items]
Line of credit facility increase in borrowing capacity	$ 200,000,000
U.S. Credit Facility \| Quarter in Final Year
Line Of Credit Facility [Line Items]
Debt instrument, quarterly periodic payment	9,400,000
U.S. Credit Facility \| Term Loan
Line Of Credit Facility [Line Items]
Lines of credit maximum borrowing capacity	250,000,000
U.S. Credit Facility \| Term Loan \| First Three Quarters
Line Of Credit Facility [Line Items]
Debt instrument, quarterly periodic payment	6,300,000
Short-Term Debt
Line Of Credit Facility [Line Items]
Lines of credit unused and available	111,800,000
Line of credit facility advanced under foreign credit line	13,300,000
Line of Credit Facility Credit Used For Guarantee	1,400,000
Short-Term Debt \| Unsecured
Line Of Credit Facility [Line Items]
Lines of credit maximum borrowing capacity	$ 126,600,000

Bank Credit Agreements and Other Short-Term and Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total long-term debt	$ 98,641	$ 215,191
Current portion of long-term debt	(33,105)	(27,613)
Less: Unamortized debt issuance costs	(1,135)	(1,435)
Long-term debt, net of current portion	64,401	186,143
Notes Payable to Bank \| Bank of Taiwan
Debt Instrument [Line Items]
Total long-term debt	4,242	4,442
Notes Payable to Bank \| Yuan Ta Bank
Debt Instrument [Line Items]
Total long-term debt		749
Notes Payable to Bank \| China Trust Bank
Debt Instrument [Line Items]
Total long-term debt	19,212
Term Loan and Revolver
Debt Instrument [Line Items]
Total long-term debt	$ 75,187	$ 210,000

Bank Credit Agreements and Other Short-Term and Long-Term Debt - Schedule of Debt (Parenthetical) (Details) - Notes Payable to Bank $ in Millions	12 Months Ended
	Dec. 31, 2019 TWD ($)
Bank of Taiwan
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 140
Long-term fixed interest rate	1.30%
Debt Instrument, maturity date, description	TWD 140 million, fixed interest rate of 1.3%, matures June 28, 2033.
Debt instrument, maturity date	Jun. 28, 2033
Yuan Ta Bank
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 113
Long-term fixed interest rate	1.70%
Debt Instrument, maturity date, description	TWD 113 million, fixed interest rate of 1.7%, matured on January 29, 2019.
Debt instrument, maturity date	Jan. 29, 2019
China Trust Bank
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 576
Long-term fixed interest rate	1.70%
Debt Instrument, maturity date, description	TWD 576 million, fixed interest rate of 1.7%, matures May 27, 2024
Debt instrument, maturity date	May 27, 2024

Bank Credit Agreements and Other Short-Term and Long-Term Debt - Schedule of Maturities of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long Term Debt By Current And Noncurrent [Abstract]
2020	$ 33,102
2021	43,620
2022	4,903
2023	1,571
2024	12,689
2025 and thereafter	2,756
Total long-term debt	$ 98,641	$ 215,191

Leases - Components of Lease Expense (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating lease expense	$ 14,824
Finance lease expense:
Amortization of assets	978
Interest on lease liabilities	48
Short-term lease expense	336
Variable lease expense	2,663
Total lease expense	$ 18,849

Leases - Supplemental Balance Sheet Information Related to Leases (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Operating leases:
Operating lease ROU assets	$ 57,427
Current operating lease liabilities	12,554
Noncurrent operating lease liabilities	27,545
Total operating lease liabilities	40,099
Finance leases:
Finance lease ROU assets	3,396
Accumulated amortization	(1,924)
Finance lease ROU assets, net	1,472
Current finance lease liabilities	903
Non-current finance lease liabilities	138
Total finance lease liabilities	$ 1,041
Weighted average remaining lease term (in years):
Operating leases	4 years 4 months 24 days
Finance leases	1 year 3 months 18 days
Weighted average discount rate:
Operating leases	3.80%
Finance leases	3.00%

Leases - Supplemental Cash Flow and Other Information Related to Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Cash paid for the amounts included in the measurements of lease liabilities:
Operating cash outflows from operating leases	$ 18,325
Operating cash outflows from finance leases	48
Financing cash outflow from finance leases	1,082
ROU assets obtained in exchange for lease liabilities incurred:
Operating leases	$ 3,956

Leases - Schedule of Operating and Finance Lease Liability Maturities (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating Leases, 2020	$ 13,779
Operating Leases, 2021	9,766
Operating Leases, 2022	8,276
Operating Leases, 2023	4,537
Operating Leases, 2024	2,433
Operating Leases, 2025	2,328
Operating Leases, 2026 and thereafter	2,573
Operating Leases, Total lease payments	43,692
Operating Leases, Less: imputed interest	(3,593)
Total operating lease liabilities	40,099
Operating Leases, Less: current obligations	(12,554)
Noncurrent operating lease liabilities	27,545
Finance Leases, 2020	922
Finance Leases, 2021	138
Finance Leases, Total lease payments	1,060
Finance Leases, Less: imputed interest	(19)
Total finance lease liabilities	1,041
Finance Leases, Less: current obligations	(903)
Non-current finance lease liabilities	$ 138

Accrued Liabilities and Other Current Liabilities, and Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities, Current [Abstract]
Accrued expenses	$ 33,733	$ 28,170
Compensation and payroll taxes	34,043	33,632
Equipment purchases	10,167	12,568
Operating lease	12,554
Finance lease	903
Accrued pricing adjustments	5,617	3,591
Accrued professional services	3,258	3,242
Other	296	1,402
Accrued Liabilities, Current, Total	100,571	82,605
Liabilities, Noncurrent [Abstract]
Accrued defined benefit plan	28,795	26,349
Unrecognized tax benefits	28,215	27,711
Operating lease	27,545
Finance lease	138
Deferred grans and subsidy	12,774	15,359
Deferred compensation	12,166	9,091
Tax contingencies	8,631	8,475
Other	2,281	3,794
Other long-term liabilities, Total	$ 120,545	$ 90,779

Stockholders' Equity - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 30, 2015
Equity Class Of Treasury Stock [Line Items]
Other Restrictions on Payment of Dividends	Our U.S. Credit Facility permits us to pay dividends up to $3.0 million per fiscal year to its stockholders so long as we have not defaulted under the U.S. Credit Facility at the time of such dividend and no default would result from declaring or paying such dividend.
Maximum annual dividend payable on credit facility conditions	$ 3,000,000.0
Stock repurchase program expiration date	Dec. 31, 2019
Common shares repurchased during period, shares	0	0	300,000
Common shares repurchased during period, value			$ 8,745,000
Stock Repurchase Program \| Maximum
Equity Class Of Treasury Stock [Line Items]
Authorized amount of common stock under stock repurchase program				$ 100,000,000

Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S.	$ 73,352	$ (24,141)	$ (72,668)
Foreign	124,894	174,103	135,259
Income before income taxes and noncontrolling interest	198,246	149,962	62,591
Current tax provision
Federal	259
Foreign	28,829	42,726	31,820
State	92	24	7
Current tax provision (benefit), Total	29,180	42,750	31,827
Deferred tax provision (benefit)
Federal	886	2,400	30,186
Foreign	11,994	(3,107)	(2,352)
State	30	56	(8)
Deferred Income Tax Expense (Benefit), Total	12,910	(651)	27,826
Liability for unrecognized tax benefits	2,041	2,457	2,672
Total income tax provision	$ 44,131	$ 44,556	$ 62,325

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Federal tax	$ 41,632	$ 31,488	$ 21,907
State income taxes, net of federal tax provision	1,389	(375)	(15)
Foreign income taxed at lower tax rates	(5,786)	(2,844)	(23,515)
U.S. tax impact of foreign operations	(3,340)	4,140	6,726
Foreign withholding taxes	22,685	10,962	4,343
Research and development	(3,686)	(3,541)	(2,643)
Liability for unrecognized tax benefits	2,041	2,457	2,672
Valuation allowance	(10,563)	(379)	2,077
Employee stock-based compensation	(52)	(2,154)	1,537
U.S. Tax Cuts and Jobs Act		2,762	45,908
Other	(189)	2,040	3,328
Total income tax provision	$ 44,131	$ 44,556	$ 62,325
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Income tax rate, Federal tax	21.00%	21.00%	35.00%
Income tax rate, State income taxes, net of federal tax provision	0.70%	(0.30%)
Income tax rate, Foreign income taxed at lower tax rates	(2.90%)	(1.90%)	(37.60%)
Income tax rate, U.S. tax impact of foreign operations	(1.70%)	2.80%	10.70%
Income tax rate, Foreign withholding taxes	11.40%	7.30%	6.90%
Income tax rate, Research and development	(1.90%)	(2.40%)	(4.20%)
Income tax rate, Liability for unrecognized tax benefits	1.00%	1.60%	4.30%
Income tax rate, Valuation allowance	(5.30%)	(0.30%)	3.30%
Income tax rate, Employee stock-based compensation	0.00%	(1.40%)	2.50%
Income tax rate, U.S. Tax Cuts and Jobs Act		1.80%	73.40%
Income tax rate, Other	(0.10%)	1.40%	5.30%
Income tax rate, Total	22.30%	29.70%	99.60%

Income Taxes - Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Beginning Balance	$ 32,209	$ 30,581	$ 28,849
Additions based on tax positions related to the current year	9,274	4,667	3,492
Additions for prior year tax positions	39		863
Reductions for prior year tax positions	(5,870)	(3,039)	(2,623)
Ending Balance	$ 35,652	$ 32,209	$ 30,581

Income Taxes - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Tax Credit Carryforward [Line Items]
Significant change in unrecognized tax benefits, nature of event	It is reasonably possible that the amount of the unrecognized benefit with respect to certain of our unrecognized tax positions will significantly increase or decrease within the next 12 months.
Significant change in unrecognized tax benefits is reasonably possible, estimated range not possible	These changes may be the result of settlements of ongoing audits or competent authority proceedings. At this time, an estimate of the range of the reasonably possible outcomes cannot be made.
Unrecognized tax benefits	$ 35,652	$ 32,209	$ 30,581	$ 28,849
Unrecognized tax benefits, if recognized, would affect the effective tax rate	$ 33,500
Income tax examination, description	We file income tax returns in the U.S. federal jurisdiction and in various state and foreign jurisdictions. We are no longer subject to U.S. federal income tax examinations by tax authorities for tax years before 2012 or tax year 2015. We are no longer subject to China income tax examinations by tax authorities for tax years before 2009. With respect to state and local jurisdictions and countries outside of the U.S., with limited exceptions, we are no longer subject to income tax audits for years before 2014. Although the outcome of tax audits is always uncertain, we believe that adequate amounts of tax, interest and penalties, if any, have been provided for in our reserve for any adjustments that may result from future tax audits. We recognize accrued interest and penalties, if any, related to unrecognized tax benefits in interest expense. We had an immaterial amount of accrued interest and penalties at December 31, 2019, 2018 and 2017.
Net deferred tax assets	$ 6,414	16,928
Tax credit carryforward, valuation allowance	8,000	19,000
Operating loss carryforward [Abstract]
Operating loss carryforwards, valuation allowance	19,000	7,000
Income taxes supplemental information [Abstract]
Statutory accounting practices, retained earnings not available for dividends	115
Additional tax on undistributed foreign earnings	46
Tax holidays	$ 3,100	$ 1,600	$ 3,700
Tax holidays basic EPS		$ 0.03	$ 0.08
Tax holidays diluted EPS	$ 0.06	$ 0.03	$ 0.08
China
Income taxes supplemental information [Abstract]
Deferred tax liabilities, undistributed foreign earnings	$ 425
State and Local Jurisdiction
Operating loss carryforward [Abstract]
Operating loss carryforwards	$ 1,000
Operating loss carryforwards, expiration dates	Jan. 01, 2020
Foreign Tax Authority
Operating loss carryforward [Abstract]
Operating loss carryforwards	$ 110,000
Operating loss carryforwards, expiration dates	Jan. 01, 2020
Income taxes supplemental information [Abstract]
Deferred tax liabilities, undistributed foreign earnings	$ 913
Federal and State Tax
Tax Credit Carryforward [Line Items]
Tax credit carryforward, amount	$ 14,000
Federal
Tax Credit Carryforward [Line Items]
Tax credit carryforward, expiration dates	Jan. 01, 2023
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Tax credit carryforward, expiration dates	Jan. 01, 2020
Research
Tax Credit Carryforward [Line Items]
Tax credit carryforward, amount	$ 8,000
ASU No. 2013-11
Tax Credit Carryforward [Line Items]
Deferred tax assets operating loss carryforwards	5,200
Deferred tax assets excluding tax benefits for operating loss carryforwards	$ 1,200

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Inventory cost	$ 10,423	$ 7,974
Accrued expenses and accounts receivable	4,420	1,866
Foreign tax credits	5,848	17,600
Research and development tax credits	16,263	15,456
Net operating loss carryforwards	24,139	9,635
Lease obligations	3,773
Accrued pension	4,629	4,294
Share based compensation and others	7,805	9,972
Total deferred tax assets, include valuation allowance	77,300	66,797
Valuation allowances	(29,414)	(25,941)
Total deferred tax assets, non-current	47,886	40,856
Deferred tax liabilities
Plant, equipment and intangible assets	(13,816)	(16,661)
Right of use assets	(4,008)
Outside basis differences and others	(23,648)	(7,267)
Total deferred tax liabilities, non-current	(41,472)	(23,928)
Net deferred tax assets	$ 6,414	$ 16,928

Employee Benefit Plans - Additional Information (Details) £ in Millions	1 Months Ended		12 Months Ended
	Oct. 31, 2018 USD ($) $ / £	Oct. 31, 2018 GBP (£) $ / £	Dec. 31, 2019 USD ($) $ / £	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 GBP (£) $ / £
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, equalization benefit, interest percentage on base rate	1.00%	1.00%
Defined benefit plan, total equalization amount	$ 700,000	£ 0.5
GBP:USD exchange rate \| $ / £	1.33	1.33
Underfunded pension and postretirement obligation, noncurrent			$ 26,100,000
Accumulated comprehensive loss defined benefit plan			44,695,000	$ 40,554,000
Defined benefit plan recognized gain loss increase(decrease)			5,100,000
Other comprehensive income (loss), pension and other postretirement benefit plans, net unamortized gain (loss) arising during period, before tax			$ 4,300,000
Defined benefit plan amortization of net gains losses average term			10 years 6 months
Defined benefit plan, expected future benefit payments in year one			$ 4,030,000
Defined benefit plan, expected future benefit payments in year two			4,592,000
Defined benefit plan, expected future benefit payments in year three			4,913,000
Defined benefit plan, expected future benefit payments in year four			5,335,000
Defined benefit plan, expected future benefit payments in year five			$ 5,668,000
Defined benefit plan, plan assets, expected long-term rate-of-return above liability benchmark			2.60%
Defined benefit plan, plan assets, expected long-term rate-of-return, description			The overall strategy is designed to return a long-term return of 2.6% p.a. above the liability benchmark which is broadly equal to changes in the plan’s liabilities.
Defined contribution plan, cost recognized			$ 16,300,000	17,000,000.0	$ 14,800,000
Deferred compensation investments			$ 12,912,000	$ 10,104,000
Deferred Compensation Plan
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation arrangements, overall, description			We maintain a Non-Qualified Deferred Compensation Plan (the “Deferred Compensation Plan”) for executive officers, key employees and members of our Board of Directors. The Deferred Compensation Plan allows eligible participants to defer the receipt of eligible compensation, including equity awards, until designated future dates. We offset our obligations under the Deferred Compensation Plan by investing in the actual underlying investments. At December 31, 2019 these investments are classified as trading securities and are carried at fair value. At December 31, 2019, these investments totaled approximately $12.9 million. All gains and losses in these investments are materially offset by corresponding gains and losses in the deferred compensation plan liabilities.
Deferred compensation investments			$ 12,900,000
United States
Defined Benefit Plan Disclosure [Line Items]
Employee salary deferral contributions percentage			100.00%
Employer matching contribution amount of match			$ 1
Defined contribution plan employee matching contribution amount			$ 2
Defined contribution plan vesting period			4 years
Description of defined contribution pension and other postretirement plans			We maintain a 401(k) retirement plan (the “Plan”) for the benefit of qualified employees at our U.S. locations. Employees who participate may elect to make salary deferral contributions to the Plan up to 100% of the employees’ eligible payroll subject to annual Internal Revenue Code maximum limitations. We currently make a matching contribution of $1 for every $2 contributed by the participant up to 6% (3% maximum matching) of the participant’s eligible payroll, which vests over an initial four years. In addition, we may make a discretionary contribution to the entire qualified employee pool, in accordance with the Plan.
TAIWAN, PROVINCE OF CHINA
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage			6.00%
Description of defined contribution pension and other postretirement plans			Pursuant to the Taiwan Labor Standard Law and Factory Law, we maintain a retirement plan for the employees in Taiwan, whereby we make contributions at a rate of 6% of the employee’s eligible payroll.
China
Defined Benefit Plan Disclosure [Line Items]
Description of defined contribution pension and other postretirement plans			As stipulated by the regulations of China, we maintain a retirement plan pursuant to the local municipal government for the employees in China. We are required to make contributions to the retirement plan at a rate between 10% and 22% of the employee’s eligible payroll.
Maximum \| United States
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage			6.00%
Employer matching contribution percent of match			3.00%
Maximum \| China
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage			22.00%
Minimum \| China
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage			10.00%
Growth Assets
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target allocation percentage of assets			65.00%			65.00%
Hedging assets
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, target allocation percentage of assets			35.00%			35.00%
Pension Plan, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, general information			In connection with the Zetex acquisition, we adopted a contributory defined benefit plan that covers certain employees in the U.K. The defined benefit plan is closed to new entrants and frozen with respect to future benefit accruals. The retirement benefit is based on the final average compensation and service of each eligible employee. We determined the fair value of the defined benefit plan assets and utilize an annual measurement date of December 31. At subsequent measurement dates, defined benefit plan assets will be determined based on fair value. Defined benefit plan assets consist of a diverse range of listed and unlisted securities including corporate bonds and mutual funds and are denominated in the currency in which the benefits will be paid and that have terms to maturity approximating the terms of the related pension liability. The net pension and supplemental retirement benefit obligations and the related periodic costs are based on, among other things, assumptions of the discount rate, estimated return on plan assets and mortality rates. These obligations and related periodic costs are measured using actuarial techniques and assumptions.
Defined benefit plan, pension, method to determine vested benefit obligation			The projected unit credit method is the actuarial cost method used to compute the pension liabilities and related expenses.
Pension Plan, Defined Benefit \| Trust for Benefit of Employee
Defined Benefit Plan Disclosure [Line Items]
GBP:USD exchange rate \| $ / £			1.33			1.33
Defined benefit plan, estimated future employer contributions in current fiscal year, description			We adopted a payment plan with the trustees of the defined benefit plan, in which we would make annual contributions each year through 2030, of approximately GBP 2 million (approximately $2.7 million based on a GBP:USD exchange rate of 1.33). The annual contributions were expected to meet the deficit disclosed in the plan as of April 5, 2013 by December 31, 2030. The trustees are required to review the funding position every three years. Following the pension plan funding valuation as at March 31, 2019 the trustees and the Company have been in discussions regarding a recovery plan would result in a plan to recover the deficit by January 1, 2029. Moving the recovery plan from a 2030 deadline to a 2029 deadline could cause us to increase our contributions. This plan has not been finalized.
Defined benefit plan, expected future benefit payments in year one			$ 2,700,000			£ 2.0
Defined benefit plan, expected future benefit payments in year two			2,700,000			2.0
Defined benefit plan, expected future benefit payments in year three			2,700,000			2.0
Defined benefit plan, expected future benefit payments in year four			2,700,000			2.0
Defined benefit plan, expected future benefit payments in year five			2,700,000			2.0
Defined benefit plan, expected future benefit payments in ten fiscal years thereafter			$ 2,700,000			£ 2.0

Employee Benefit Plans - Net periodic benefit costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 256	$ 267
Interest cost	4,069	4,151
Recognized actuarial loss	1,546	2,625
Expected return on plan assets	(7,511)	(7,339)
Prior service cost	55
Net periodic benefit cost	$ (1,585)	$ (296)

Employee Benefit Plans - Schedule of Benefit Obligation, Fair Value of Plan Assets, and Funded Status of our Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Change in Benefit Obligation [Roll Forward]
Service cost	$ 256	$ 267
Interest cost	4,069	4,151
Change in Plan Assets [Roll Forward]
Fair value of plan assets - ending	132,621
Pension Plan, Defined Benefit
Change in Benefit Obligation [Roll Forward]
Benefit obligation - beginning	141,104	166,063
Service cost	255	267
Interest cost	4,045	4,151
Actuarial loss (gain)	11,214	(9,827)
Benefits paid	(4,158)	(3,625)
Settlements		(7,471)
Currency changes	6,220	(8,454)
Benefit obligation - ending	158,680	141,104
Change in Plan Assets [Roll Forward]
Fair value of plan assets - beginning	117,162	134,234
Employer contribution	2,629	2,796
Actual return on plan assets	11,791	(2,084)
Benefits paid	(4,158)	(3,625)
Settlements		(6,731)
Currency changes	5,197	(7,428)
Fair value of plan assets - ending	132,621	117,162
Underfunded status	$ (26,059)	$ (23,942)

Employee Benefit Plans - Expected future benefit payments (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Defined Benefit Plan Estimated Future Benefit Payments [Abstract]
2020	$ 4,030
2021	4,592
2022	4,913
2023	5,335
2024	5,668
2025-2029	$ 29,846

Employee Benefit Plans - Plan Assets by major categories (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 132,621
Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	14,057
Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	118,564
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	14,057
Cash and Cash Equivalents \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	14,057
Equity Securities, U.K.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	683
Equity Securities, U.K. \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	683
Equity Securities, Overseas Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5,909
Equity Securities, Overseas Equities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5,909
Equity Securities, Emerging Markets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	11,413
Equity Securities, Emerging Markets \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	11,413
Fixed Income Securities, Government Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5,160
Fixed Income Securities, Government Bonds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5,160
Fixed Income Securities, Non-Government Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	9,906
Fixed Income Securities, Non-Government Bonds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	9,906
Index Linked Securities, U.K. Treasury Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	166
Index Linked Securities, U.K. Treasury Securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	166
Hedge Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	39,710
Hedge Funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	39,710
Property
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3,224
Property \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3,224
Liability Driven Investments
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	42,014
Liability Driven Investments \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	42,014
Other
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	379
Other \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 379

Share-Based Compensation - Additional Information (Details)	1 Months Ended		12 Months Ended
	May 31, 2017 shares	May 31, 2013 shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) CorporateOfficer shares	Dec. 31, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, fair value assumptions, method used			Share-based compensation expense for stock options granted in previous years was calculated on the date of grant using the Black-Scholes-Merton option-pricing model
Stock options granted, shares			0	0
Cash proceeds received from stock option exercises \| $			$ 11,900,000	$ 4,900,000	$ 13,600,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized \| $			$ 40,000,000.0
Share-based compensation arrangement by share-based payment award, award granted in period			670,000	646,000	746,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition			2 years 2 months 12 days
Aggregate fair value amount of shares vested \| $			$ 20,700
Corporate Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees impacted by stock modification \| CorporateOfficer				2
Corporate Officers \| Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental expense \| $				$ 1,800,000
Performance Grants \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage of award subject to performance criteria					200.00%
Performance-based grant covering shares					125,810
Incremental expense \| $					$ 3,300,000
Performance Grants \| Chief Executive Officer \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based grant covering shares, description			During 2017, the Company modified a performance-based award previously granted to our Chief Executive Officer.
Performance Grants \| Chief Executive Officer \| Common Stock \| Previous Performance Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award granted in period					700,000
Performance Grants \| Chief Executive Officer \| Common Stock \| Current Performance Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award granted in period					62,905
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized \| $			$ 0
Stock Options \| Corporate Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock modification, number of shares subject to accelerated vesting				7,500
Stock Options \| Plan 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, description			Stock options under the 2013 Plan generally vest in equal annual installments over a four-year period and expire eight years after the grant date
Share-based compensation arrangement by share-based payment award, award vesting period		4 years
Share-based compensation arrangement by share-based payment award, expiration period		8 years
Share-based compensation arrangement by share-based payment award, number of shares authorized	12,000,000	6,000,000
Share-based compensation arrangement by share-based payment award, number of additional shares authorized	6,000,000
Restricted Stock Awards and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period			4 years
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition			4 years
Restricted Stock Awards and Restricted Stock Units \| Plan 2001
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award granted in period			0
Restricted Stock \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental expense \| $					$ 1,700,000
Restricted Stock \| Chief Executive Officer \| Common Stock \| Current Performance Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award granted in period					62,905
Stock Awards \| Corporate Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock modification, number of shares subject to accelerated vesting				79,720
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period			3 years
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition			3 years

Share-Based Compensation - Schedule of Share Based Compensation Stock Options Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Options, Shares:
Outstanding Beginning Shares	988	1,228	1,833
Exercised Shares	(524)	(240)	(581)
Forfeited or Expired Shares			(24)
Outstanding Ending Shares	464	988	1,228
Shares Exercisable	464
Weighted Average Exercise Price:
Outstanding Beginning Weighted Average Exercise Price	$ 23.47	$ 22.85	$ 23.08
Exercised Weighted Average Exercise Price	22.68	20.28	23.42
Forfeited or Expired Weighted Average Exercise Price			26.87
Outstanding Ending Weighted Average Exercise Price	24.37	$ 23.47	$ 22.85
Exercisable Weighted Average Exercise Price	$ 24.37
Weighted Average Remaining Contractual Term:
Outstanding Weighted Average Remaining Contractual Term	2 years
Exercisable Weighted Average Remaining Contractual Term	2 years
Aggregate Intrinsic Value :
Exercised Aggregate Intrinsic Value	$ 10,600
Outstanding Aggregate Intrinsic Value	14,849
Exercisable Aggregate Intrinsic Value	$ 14,849

Share Based Compensation - Schedule of Stock Options Outstanding (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Options Outstanding [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	464
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 24.37	$ 23.47	$ 22.85	$ 23.08
Plan 2001
Stock Options Outstanding [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	15.05
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	$ 29.21
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	259
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 23.17
Plan 2013
Stock Options Outstanding [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	23.35
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	$ 27.92
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	205
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 25.91

Share-Based Compensation - Schedule of Nonvested Restricted and Performance Stock Units Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary of the status of non vested share grants [Roll Forward]
Beginning balance nonvested	1,667	2,280	2,620
Granted	670	646	746
Vested	(573)	(1,213)	(645)
Forfeited	(67)	(46)	(441)
Ending balance nonvested	1,697	1,667	2,280
Weighted-Average Grant-Date Fair Value [Roll Forward]
Beginning balance nonvested	$ 26.68	$ 22.24	$ 21.31
Granted	38.15	32.06	25.23
Vested	24.90	21.39	21.89
Forfeited	30.44	24.72	22.31
Ending balance nonvested	$ 31.71	$ 26.68	$ 22.24
Aggregate Intrinsic Value
Vested	$ 20,682
Balance nonvested	$ 95,687

Related Party Transactions - Additional Information (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 $ / shares
Lite On Semiconductor
Related Party Transaction [Line Items]
Business acquisition, conversion price \| (per share)	$ 1.42			$ 42.50
Cash payments to acquire business	$ 437.0
Lite On Semiconductor
Related Party Transaction [Line Items]
Related Party ownership of common stock	15.20%			15.20%
Related Party Transaction, Description of Transaction	LSC is our largest stockholder, owning approximately 15.2% of our outstanding Common Stock as of December 31, 2019, and is a member of the Lite-On Group of companies.
Lite On Semiconductor \| Maximum
Related Party Transaction [Line Items]
Related Party Transaction Revenues Percentage from Transactions with Related Party	1.00%	1.00%	1.00%
Keylink
Related Party Transaction [Line Items]
Related Party ownership of common stock	5.00%			5.00%
Related Party Transaction, Description of Transaction	Keylink is our 5% partner in our Shanghai assembly and test facilities.
Related Party Transaction Revenues Percentage from Transactions with Related Party	1.00%	1.00%	1.00%
Related Party Transaction Consulting Fees from Transactions with Related Party	$ 15.3	$ 16.6	$ 17.1
Chengdu Ya Guang Electronic Company Limited ("Ya Guang")
Related Party Transaction [Line Items]
Related Party Transaction, Description of Transaction	In addition, Chengdu Ya Guang Electronic Company Limited (“Ya Guang”) is our 2% partner in one of our Chengdu assembly and test facilities and our 5% partner in our other Chengdu assembly and test facilities
Chengdu Ya Guang Electronic Company Limited ("Ya Guang") \| Chengdu \| Assembly and Test Facility One
Related Party Transaction [Line Items]
Related Party ownership of common stock	2.00%			2.00%
Chengdu Ya Guang Electronic Company Limited ("Ya Guang") \| Chengdu \| Assembly and Test Facility Two
Related Party Transaction [Line Items]
Related Party ownership of common stock	5.00%			5.00%

Related Party Transactions - Schedule of Account Receivable and Payable of Related Party Transactions (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
LSE, its Subsidiaries and Affiliates
Related Party Transaction [Line Items]
Accounts receivable	$ 184	$ 286
Accounts payable	2,154	2,696
Keylink
Related Party Transaction [Line Items]
Accounts receivable	31,598	6,264
Accounts payable	28,244	4,656
Nuvoton
Related Party Transaction [Line Items]
Accounts payable	1,055	1,939
JCP
Related Party Transaction [Line Items]
Accounts payable	$ 173	$ 151

Segment Information, Revenue and Enterprise-Wide Disclosures - Schedule of Net Sales From Based on Location of the Subsidiary (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Net sales	$ 301,157	$ 323,674	$ 322,006	$ 302,293	$ 314,446	$ 320,946	$ 304,085	$ 274,512	$ 1,249,130	$ 1,213,989	$ 1,054,204
Property, plant and equipment, net	469,574				446,835				469,574	446,835	459,169
Total assets	1,639,384				1,526,371				1,639,384	1,526,371	1,488,673
Operating Segments
Segment Reporting Information [Line Items]
Net sales									2,081,539	1,443,933	1,315,688
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales									(832,409)	(229,944)	(261,484)
Asia
Segment Reporting Information [Line Items]
Net sales									816,373	918,647	839,796
Property, plant and equipment, net	379,075				392,445				379,075	392,445	390,850
Total assets	1,207,331				1,095,037				1,207,331	1,095,037	1,061,686
Asia \| Operating Segments
Segment Reporting Information [Line Items]
Net sales									1,234,750	1,069,068	968,720
Asia \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales									(418,377)	(150,421)	(128,924)
North America
Segment Reporting Information [Line Items]
Net sales									291,951	155,137	100,356
Property, plant and equipment, net	23,104				30,507				23,104	30,507	44,523
Total assets	216,250				240,540				216,250	240,540	230,997
North America \| Operating Segments
Segment Reporting Information [Line Items]
Net sales									612,697	179,459	171,964
North America \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales									(320,746)	(24,322)	(71,608)
Europe
Segment Reporting Information [Line Items]
Net sales									140,806	140,205	114,052
Property, plant and equipment, net	67,395				23,883				67,395	23,883	23,796
Total assets	$ 215,803				$ 190,794				215,803	190,794	195,990
Europe \| Operating Segments
Segment Reporting Information [Line Items]
Net sales									234,092	195,406	175,004
Europe \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Net sales									$ (93,286)	$ (55,201)	$ (60,952)

Segment Information, Revenue and Enterprise-Wide Disclosures - Schedule of Net Sales by Direct Sales or Distributor and Location (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2019

Dec. 31, 2018

Dec. 31, 2017

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 301,157

$ 323,674

$ 322,006

$ 302,293

$ 314,446

$ 320,946

$ 304,085

$ 274,512

$ 1,249,130

$ 1,213,989

$ 1,054,204

Percentage of net sales

100.00%

Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 407,851

$ 346,997

$ 334,455

Percentage of net sales

100.00%

Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 841,279

$ 866,992

$ 719,749

Percentage of net sales

100.00%

China

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 633,799

$ 662,625

$ 593,127

Percentage of net sales

51.00%

55.00%

56.00%

China | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 228,822

$ 226,360

$ 220,390

Percentage of net sales

56.00%

65.00%

66.00%

China | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 404,977

$ 436,265

$ 372,737

Percentage of net sales

48.00%

50.00%

52.00%

United States

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 100,596

$ 120,242

$ 86,277

Percentage of net sales

8.00%

10.00%

8.00%

United States | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 10,161

$ 15,644

$ 16,522

Percentage of net sales

2.00%

5.00%

United States | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 90,435

$ 104,598

$ 69,755

Percentage of net sales

11.00%

12.00%

10.00%

Korea

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 60,368

$ 63,960

$ 65,848

Percentage of net sales

5.00%

6.00%

Korea | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 22,099

$ 16,562

$ 17,765

Percentage of net sales

5.00%

Korea | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 38,269

$ 47,398

$ 48,083

Percentage of net sales

5.00%

7.00%

Germany

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 78,055

$ 93,714

$ 74,302

Percentage of net sales

6.00%

8.00%

7.00%

Germany | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 11,559

$ 11,770

$ 10,879

Percentage of net sales

3.00%

Germany | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 66,496

$ 81,944

$ 63,423

Percentage of net sales

8.00%

9.00%

Singapore

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 67,513

$ 68,153

$ 58,570

Percentage of net sales

5.00%

6.00%

Singapore | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 568

$ 2,150

$ 873

Percentage of net sales

1.00%

Singapore | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 66,945

$ 66,003

$ 57,697

Percentage of net sales

8.00%

Taiwan

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 93,501

$ 76,344

$ 67,369

Percentage of net sales

7.00%

6.00%

Taiwan | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 2,748

$ 2,846

$ 6,327

Percentage of net sales

1.00%

2.00%

Taiwan | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

$ 90,753

$ 73,498

$ 61,042

Percentage of net sales

11.00%

8.00%

All Others

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

^[1]

$ 215,298

$ 128,951

$ 108,711

Percentage of net sales

^[1]

18.00%

10.00%

11.00%

All Others | Direct Sales

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

^[1]

$ 131,894

$ 71,665

$ 61,699

Percentage of net sales

^[1]

33.00%

20.00%

19.00%

All Others | Distributor

Segment Reporting Revenue Reconciling Item [Line Items]

Net sales

^[1]

$ 83,404

$ 57,286

$ 47,012

Percentage of net sales

^[1]

9.00%

8.00%

6.00%

[1]	Represents countries with less than 3% of the total net sales of each.

Segment Information, Revenue and Enterprise-Wide Disclosures - Schedule of Net Sales by Direct Sales or Distributor and Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales	$ 301,157	$ 323,674	$ 322,006	$ 302,293	$ 314,446	$ 320,946	$ 304,085	$ 274,512	$ 1,249,130	$ 1,213,989	$ 1,054,204
Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									407,851	346,997	334,455
Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									841,279	866,992	719,749
Total Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									1,249,130	1,213,989	1,054,204
Asia
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									816,373	918,647	839,796
Asia \| Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									316,962	292,459	285,610
Asia \| Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									625,615	651,659	563,661
Asia \| Total Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									942,577	944,118	849,271
Americas \| Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									27,443	26,296	23,696
Americas \| Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									98,095	105,458	69,755
Americas \| Total Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									125,538	131,754	93,451
Europe
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									140,806	140,205	114,052
Europe \| Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									63,446	28,242	25,149
Europe \| Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									117,569	109,875	86,333
Europe \| Total Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 181,015	$ 138,117	$ 111,482

Segment Information, Revenue and Enterprise-Wide Disclosures - Additional Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Customer	Dec. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($) Customer
Entity Wide Revenue Major Customer [Line Items]
Number of customer accounted for 10.0% or $119.6 million, $120.0 million and $101.7 million of revenue \| Customer									1	1	1
Percentage of net sales									100.00%	100.00%	100.00%
Concentration risk, revenue amount \| $	$ 301,157	$ 323,674	$ 322,006	$ 302,293	$ 314,446	$ 320,946	$ 304,085	$ 274,512	$ 1,249,130	$ 1,213,989	$ 1,054,204
Number of customer did not account for 10% or greater of outstanding accounts receivable \| Customer									0	0
Geographic Concentration Risk
Entity Wide Revenue Major Customer [Line Items]
Percentage of net sales									10.00%	10.00%	10.00%
Concentration risk, revenue amount \| $									$ 119,600	$ 120,000	$ 101,700

Commitments and Contingencies - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Commitments And Contingencies [Line Items]
Purchase Commitments	$ 30.0
Long-term Purchase Commitment, Amount	63.6
Equity Investment Obligation \| Chengdu
Commitments And Contingencies [Line Items]
Purchase obligation in 2020	25.0
Capital Investment Obligation \| Chengdu
Commitments And Contingencies [Line Items]
Purchase obligation in 2020	25.0
Purchase obligation in 2021	$ 16.0

Derivative Financial Instruments - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Objectives for using derivative instruments	The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps, including interest rate collars, as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount.
Net derivative gain will be reclassified from AOCI into net income	$ 300,000
Fair value of derivatives in net asset position	100,000	$ 4,700,000
Posted collateral related to agreements	0	0
Foreign Currency Forward Contracts
Derivative [Line Items]
Fair value of foreign exchange hedges	0	0
Total notional amount of foreign exchange contracts	$ 106,000,000.0	$ 122,400,000

- Definition

Description of the reasons for holding or issuing derivative instruments and nonderivative hedging instruments. Includes discussion of the objectives for holding or issuing derivative instruments, the context needed to understand those objectives, and the strategies for achieving those objectives. The description generally distinguishes between derivative and nonderivative instruments by the types of hedging relationships and between those instruments used for risk management purposes and those used for other purposes. Information about those instruments is disclosed in the context of each instrument's primary underlying risk exposure (for example, interest rate, credit, foreign exchange rate, interest rate and foreign exchange rate, or overall price).

+ References + Details

Derivative Financial Instruments - Summary of Outstanding Foreign Currency Forward Contracts (Details) - Foreign Currency Forward Contracts	12 Months Ended
	Dec. 31, 2019 USD ($) € / £ € / $ £ / $ $ / ¥ $ / ¥ $ / $	Dec. 31, 2018 USD ($) € / £ € / $ £ / $ $ / ¥ $ / ¥ $ / $
Derivative [Line Items]
Notional Amount	$ 106,000,000.0	$ 122,400,000
Derivative One \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 1,844,000	$ 1,221,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	EUR/GPB	EUR/GPB
Weighted Average Strike Rate \| € / £	0.8471	0.8981
Derivative Two \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 3,375,000	$ 12,538,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	EUR/USD	EUR/USD
Weighted Average Strike Rate \| € / $	1.123	1.1479
Derivative Three \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 25,957,000	$ 8,463,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	GPB/USD	GPB/USD
Weighted Average Strike Rate \| £ / $	1.3257	1.2785
Derivative Four \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 39,340,000	$ 44,946,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	USD/CNY	USD/CNY
Weighted Average Strike Rate \| $ / ¥	6.9762	6.8738
Derivative Five \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 763,000	$ 844,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	USD/JPY	USD/JPY
Weighted Average Strike Rate \| $ / ¥	108.732	110.14
Derivative Six \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 33,621,000	$ 54,041,000
Effective Date	Dec. 31, 2019	Dec. 31, 2018
Maturity Date	Feb. 29, 2020	Feb. 28, 2019
Index	USD/TWD	USD/TWD
Weighted Average Strike Rate \| $ / $	29.988	30.559
Derivative Seven \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 500,000	$ 300,000
Effective Date	Jan. 31, 2019	Dec. 31, 2018
Maturity Date	Jan. 31, 2020	Jan. 31, 2019
Index	USD/TWD	USD/TWD
Weighted Average Strike Rate \| $ / $	30.635	30.669
Derivative Eight \| Cash Flow Hedges \| Non-designated
Derivative [Line Items]
Notional Amount	$ 500,000
Effective Date	Oct. 31, 2019
Maturity Date	Feb. 29, 2020
Index	USD/TWD
Weighted Average Strike Rate \| $ / $	30.571

Derivative Financial Instruments - Summary of Fair Value of Interest Rate Related Derivative Financial Instruments and Their Classification on Consolidated Balance Sheets (Details) - Interest Rate Swaps and Collars - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Fair value of derivative instruments, asset derivatives	$ 51
Designated as Hedging Instrument \| Other Current Assets
Derivative [Line Items]
Fair value of derivative instruments, asset derivatives	194	$ 1,936
Designated as Hedging Instrument \| Other Assets
Derivative [Line Items]
Fair value of derivative instruments, asset derivatives	36	$ 2,795
Designated as Hedging Instrument \| Other Current Liabilities
Derivative [Line Items]
Fair value of derivative instruments, liability derivatives	51
Designated as Hedging Instrument \| Other Liabilities
Derivative [Line Items]
Fair value of derivative instruments, liability derivatives	$ 127

Derivative Financial Instruments - Summary of Effect of Derivative Financial Instruments on Consolidated Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Designated as Hedging Instrument \| Interest Rate Swaps and Collars
Derivative Instruments Gain Loss [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative	$ (2,997)	$ 1,790	$ 1,567
Location of Gain or (Loss) Reclassified from Accumulated OCI into Income	Interest expense
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Net Income	$ 1,248	860	577
Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion Excluded from Effectiveness Testing)	N/A
Designated as Hedging Instrument \| Cross Currency Swaps
Derivative Instruments Gain Loss [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative	$ (298)
Location of Gain or (Loss) Reclassified from Accumulated OCI into Income	N/A
Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion Excluded from Effectiveness Testing)	Interest income
Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	$ 688
Not Designated as Hedging Instrument \| Foreign Currency Forward Contracts
Derivative Instruments Gain Loss [Line Items]
Amount of Gain or (Loss) Recognized in Net Income	$ (3,662)	$ (8,493)	$ 1,491
Location of Gain or (Loss) Recognized in Net Income	Foreign currency loss, net

Restructuring Costs - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Assets impairement related to KFAB shut-down		$ 390	$ 2,211
KFAB Wafer Manufacturing Operations
Restructuring Cost And Reserve [Line Items]
Restructuring activities description	In February 2017, the Company announced its plan to transfer its wafer fabrication operation at KFAB to other Company-owned wafer fabrication plants and external foundries. The Company ceased production operations at KFAB late in third quarter 2017, and vacated and returned the premises to the landlord in November 2017.
Proceeds from insurance settlement		3,700	6,500
Assets impairement related to KFAB shut-down			1,900
Additional asset retirement obligations related to restructuring			1,403
KFAB Wafer Manufacturing Operations \| Cost of Goods Sold
Restructuring Cost And Reserve [Line Items]
Proceeds from insurance settlement			4,500
KFAB Wafer Manufacturing Operations \| Other Income
Restructuring Cost And Reserve [Line Items]
Proceeds from insurance settlement		$ 3,700	$ 2,000

Restructuring Costs - Schedule of Restructuring Costs, Recorded in Restructuring Expense in Condensed Consolidated Statements of Operations, Incurred (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown	$ 206	$ 10,137
KFAB Wafer Manufacturing Operations
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown	206	10,137
KFAB Wafer Manufacturing Operations \| Early Supply Contract Termination
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown		1,985
KFAB Wafer Manufacturing Operations \| Cost of Equipment Relocation, Shutdown Cost and Other
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown	220	3,591
KFAB Wafer Manufacturing Operations \| Asset Retirement Obligation
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown		1,403
KFAB Wafer Manufacturing Operations \| Retention Costs
Restructuring Cost And Reserve [Line Items]
Restructuring costs relating to KFAB shutdown	$ (14)	$ 3,158

Restructuring Costs - Schedule of Costs Accrued Related to Restructuring (Details) - KFAB Wafer Manufacturing Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Beginning balance, January 1, 2017	$ 1,304
Costs accrued	512	$ 8,734
Restructuring costs paid	(1,816)	(7,430)
Balance at December 31, 2017		1,304
Early Contract Termination
Restructuring Cost And Reserve [Line Items]
Costs accrued		1,985
Restructuring costs paid		(1,985)
Retention Costs
Restructuring Cost And Reserve [Line Items]
Beginning balance, January 1, 2017	659
Costs accrued	(14)	3,158
Restructuring costs paid	(645)	(2,499)
Balance at December 31, 2017		659
Equipment Relocation, Shutdown Cost and Other
Restructuring Cost And Reserve [Line Items]
Beginning balance, January 1, 2017	645
Costs accrued	526	3,591
Restructuring costs paid	$ (1,171)	(2,946)
Balance at December 31, 2017		$ 645

Business Acquisitions - Additional Information (Details) $ / shares in Units, $ in Thousands			3 Months Ended		12 Months Ended
	Apr. 01, 2019 USD ($)	Jul. 31, 2018 USD ($)	Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2019 $ / shares	Dec. 31, 2019 USD ($)
ERIS Technology Corporation
Business Acquisition [Line Items]
Ownership percentage in subsidiary		51.00%
Wafer Fabrication Facility ("GFAB")
Business Acquisition [Line Items]
Acquisition date	Apr. 01, 2019
Business acquisition aggregate consideration	$ 33,200
Wafer Fabrication Facility ("GFAB") \| Selling, General and Administrative
Business Acquisition [Line Items]
Acquisition costs	$ 600
LSC Acquisition
Business Acquisition [Line Items]
Business acquisition aggregate consideration			$ 437,000
Exchange rights value of shares \| (per share)			$ 1.42	$ 42.50
Cash payments to acquire business					$ 437,000
Yea Shin Technology Co Ltd \| ERIS Technology Corporation
Business Acquisition [Line Items]
Percentage of shares acquired by subsidiary in acquiree		51.00%			51.00%
Cash payments to acquire business		$ 6,400
Yong Xiang Development Corporation \| ERIS Technology Corporation
Business Acquisition [Line Items]
Total purchase price for business acquisition		25,500
Lease monthly payment for first 8.5 months		40
Lease monthly payment for the remaining period		$ 30

Business Acquisitions - Summary of Fair Value of Assets and Liabilities Related to Acquisition Recorded in Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Apr. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill	$ 141,318		$ 132,437	$ 134,187
Wafer Fabrication Facility ("GFAB")
Business Acquisition [Line Items]
Property, plant and equipment		$ 24,400
Inventories		3,600
Prepaid expenses and other		5,200
Goodwill		900
Deferred tax liabilities		$ 1,000

Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Selected Quarterly Financial Information [Abstract]
Net sales	$ 301,157	$ 323,674	$ 322,006	$ 302,293	$ 314,446	$ 320,946	$ 304,085	$ 274,512	$ 1,249,130	$ 1,213,989	$ 1,054,204
Gross profit	109,362	122,046	121,988	112,411	114,199	115,214	107,268	98,595	465,807	435,276	356,776
Net income (loss) attributable to common shareholders	$ 47,190	$ 38,060	$ 36,284	$ 31,716	$ 29,519	$ 30,908	$ 25,068	$ 18,526	$ 153,250	$ 104,021	$ (1,805)
Earnings (loss) per share attributable to common shareholders
Basic	$ 0.92	$ 0.75	$ 0.72	$ 0.63	$ 0.59	$ 0.62	$ 0.50	$ 0.38	$ 3.02	$ 2.09	$ (0.04)
Diluted	$ 0.90	$ 0.73	$ 0.70	$ 0.62	$ 0.58	$ 0.61	$ 0.49	$ 0.37	$ 2.96	$ 2.04	$ (0.04)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Subsequent Event - Additional Information - (Details) - Savitech Corporation (“Savitech”)	Feb. 05, 2020 USD ($) Tranche	Jun. 30, 2021 USD ($)
Scenario Forecast
Subsequent Event [Line Items]
Percentage of shares acquired by subsidiary in acquiree		51.00%
Scenario Forecast \| Maximum
Subsequent Event [Line Items]
Percentage of shares acquired by subsidiary in acquiree		51.00%
Subsequent Event
Subsequent Event [Line Items]
Number of tranche investment \| Tranche	2
Subsequent Event \| Maximum
Subsequent Event [Line Items]
Agreement amount to be invested	$ 14,200,000
Tranche One \| Scenario Forecast
Subsequent Event [Line Items]
Investment amount		$ 5,600,000
Ownership percentage acquired		32.00%
Tranche Two \| Scenario Forecast
Subsequent Event [Line Items]
Investment amount		$ 8,600,000

Summary of Operations and Significant Accounting Policies - Component of Comprehensive Income (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Unrealized foreign currency losses	$ (63,053)	$ (64,553)
Unrealized gain on interest rate swap, net of tax	(391)	3,261
Unrealized loss on defined benefit plan	$ (44,695)	$ (40,554)

Earnings Per Share - Additional Information (Details)	12 Months Ended
Earnings Per Share - Additional Information (Details)	Dec. 31, 2019
Earnings Per Share [Abstract]
Earnings per share reconciliation disclosure	Basic earnings per share is calculated by dividing net earnings attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is calculated similarly but includes potential dilution from the exercise of stock options and stock awards, except when the effect would be anti-dilutive.

Employee Benefit Plans - Schedule of Assumptions Used (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined benefit plan, Weighted average assumptions used in calculating net periodic benefit cost [Abstract]
Expected long-term return on plan assets	5.60%
Pension Plan, Defined Benefit
Defined benefit plan, Weighted average assumptions used in calculating net periodic benefit cost [Abstract]
Discount rate	2.90%	2.60%
Expected long-term return on plan assets	6.40%	5.60%
Defined benefit plan, Weighted average assumptions used in calculating benefit obligation [Abstract]
Discount rate	2.00%	2.90%

Employee Benefit Plans - Expected long-term return by asset category (Details)	12 Months Ended
	Dec. 31, 2019
Expected Long Term Return [Abstract]
Expected long-term return	5.60%
Asset allocation [Abstract]
Asset allocation	100.00%
Growth assets
Expected Long Term Return [Abstract]
Expected long-term return	7.80%
Asset allocation [Abstract]
Asset allocation	70.00%
Hedging assets
Expected Long Term Return [Abstract]
Expected long-term return	1.30%
Asset allocation [Abstract]
Asset allocation	27.00%
Cash
Expected Long Term Return [Abstract]
Expected long-term return	0.80%
Asset allocation [Abstract]
Asset allocation	3.00%

Derivative Financial Instruments - Summary of Information Related to Number of and Notional Amount of Interest Rate Related Derivative Instruments (Details) - Interest Rate Swaps and Collars - Designated as Hedging Instrument	Dec. 31, 2019 USD ($) DerivativeInstrument	Dec. 31, 2018 USD ($) DerivativeInstrument
Derivative [Line Items]
Number of Instruments \| DerivativeInstrument	9	12
Notional Amount \| $	$ 200,000,000	$ 210,000,000