Littelfuse (LFUS) 10-Q 28 Oct 20 2020 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 26, 2020	Oct. 23, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 26, 2020
Document Transition Report	false
Entity File Number	0-20388
Entity Registrant Name	LITTELFUSE INC /DE
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-3795742
Entity Address, Address Line One	8755 West Higgins Road
Entity Address, Address Line Two	Suite 500
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60631
City Area Code	773
Local Phone Number	628-1000
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	LFUS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		24,375,049
Entity Central Index Key	0000889331
Current Fiscal Year End Date	--12-26
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Current assets:
Cash and cash equivalents	$ 641,890	$ 531,139
Short-term investments	52	44
Trade receivables, less allowances of $42,737 and $42,043 at September 26, 2020 and December 28, 2019, respectively	231,930	202,309
Inventories	243,832	237,507
Prepaid income taxes and income taxes receivable	1,218	4,831
Prepaid expenses and other current assets	30,012	28,564
Total current assets	1,148,934	1,004,394
Net property, plant, and equipment	339,870	344,617
Intangible assets, net of amortization	296,159	321,247
Goodwill	799,791	820,589
Investments	26,066	24,099
Deferred income taxes	7,173	8,069
Right of use lease assets, net	18,811	21,918
Other assets	17,566	14,965
Total assets	2,654,370	2,559,898
Current liabilities:
Accounts payable	120,938	117,320
Accrued liabilities	98,437	84,120
Accrued income taxes	15,231	14,122
Current portion of long-term debt	0	10,000
Total current liabilities	234,606	225,562
Long-term debt, less current portion	725,507	669,158
Deferred income taxes	46,584	49,763
Accrued post-retirement benefits	40,279	38,198
Non-current operating lease liabilities	14,193	17,166
Other long-term liabilities	63,639	64,037
Shareholders’ equity:
Common stock, par value $0.01 per share: 34,000,000 shares authorized; shares issued, September 26, 2020–26,015,067; December 28, 2019–25,855,203	258	256
Treasury stock, at cost: 1,644,103 and 1,473,901 shares, respectively	(242,323)	(216,447)
Additional paid-in capital	891,924	867,996
Accumulated other comprehensive loss	(107,238)	(106,823)
Retained earnings	986,810	950,901
Littelfuse, Inc. shareholders’ equity	1,529,431	1,495,883
Non-controlling interest	131	131
Total equity	1,529,562	1,496,014
Total liabilities and equity	$ 2,654,370	$ 2,559,898

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Statement of Financial Position [Abstract]
Allowance for trade receivables	$ 42,737	$ 42,043
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	34,000,000	34,000,000
Common stock issued (in shares)	26,015,067	25,855,203
Treasury stock (in shares)	1,644,103	1,473,901

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF NET INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Income Statement [Abstract]
Net sales	$ 391,566	$ 361,971	$ 1,044,999	$ 1,165,350
Cost of sales	253,390	231,025	684,012	737,368
Gross profit	138,176	130,946	360,987	427,982
Selling, general, and administrative expenses	50,465	54,224	158,832	174,845
Goodwill impairment charge	0	0	33,841	0
Research and development expenses	13,049	19,728	41,044	62,595
Amortization of intangibles	10,104	9,827	29,912	30,068
Total operating expenses	73,618	83,779	263,629	267,508
Operating income	64,558	47,167	97,358	160,474
Interest expense	4,988	5,559	16,261	16,834
Foreign exchange (gain) loss	(6,174)	4,968	(9,600)	5,636
Other income, net	(1,682)	(4,764)	(1,643)	(3,406)
Income before income taxes	67,426	41,404	92,340	141,410
Income taxes	12,070	5,757	21,331	24,982
Net income	$ 55,356	$ 35,647	$ 71,009	$ 116,428
Income per share:
Basic (in dollars per share)	$ 2.27	$ 1.46	$ 2.92	$ 4.72
Diluted (in dollars per share)	$ 2.25	$ 1.44	$ 2.89	$ 4.68
Weighted-average shares and equivalent shares outstanding:
Basic (in shares)	24,357	24,482	24,354	24,646
Diluted (in shares)	24,573	24,684	24,535	24,894

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 55,356	$ 35,647	$ 71,009	$ 116,428
Other comprehensive income (loss):
Pension and postemployment adjustment, net of tax	563	137	(9,715)	249
Foreign currency translation adjustments	16,418	(17,163)	9,300	(14,933)
Comprehensive income	$ 72,337	$ 18,621	$ 70,594	$ 101,744

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019
OPERATING ACTIVITIES
Net income	$ 71,009	$ 116,428
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	41,953	38,988
Amortization of intangibles	29,912	30,068
Deferred revenue	(438)	(228)
Impairment charges	36,078	322
Stock-based compensation	14,544	15,738
(Gain) loss on investments and other assets	(1,200)	559
Deferred income taxes	1,567	(203)
Other	(8,549)	8,267
Changes in operating assets and liabilities:
Trade receivables	(29,362)	2,781
Inventories	(1,611)	18,102
Accounts payable	6,661	(29,453)
Accrued liabilities and income taxes	(2,095)	(44,241)
Prepaid expenses and other assets	5,787	3,735
Net cash provided by operating activities	164,256	160,863
INVESTING ACTIVITIES
Acquisitions of businesses, net of cash acquired	0	(775)
Purchases of property, plant, and equipment	(41,536)	(38,397)
Net proceeds from sale of property, plant and equipment	148	6,212
Net cash used in investing activities	(41,388)	(32,960)
FINANCING ACTIVITIES
Proceeds of revolving credit facility	240,000	0
Payments of revolving credit facility	(60,000)	0
Payments of term loan	(145,000)	(7,500)
Net proceeds related to stock-based award activities	6,437	4,412
Purchases of common stock	(22,927)	(99,387)
Debt issuance costs	(1,786)	0
Cash dividends paid	(35,100)	(32,990)
Net cash used in financing activities	(18,376)	(135,465)
Effect of exchange rate changes on cash and cash equivalents	6,259	(6,114)
Increase (decrease) in cash and cash equivalents	110,751	(13,676)
Cash and cash equivalents at beginning of period	531,139	489,733
Cash and cash equivalents at end of period	641,890	476,057
Supplementary Cash Flow Information
Cash paid during the period for interest	17,228	17,872
Capital expenditures, not yet paid	$ 6,267	$ 8,978

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Addl. Paid in Capital	Treasury Stock	Accum. Other Comp. (Loss) Income	Retained Earnings	Non-controlling Interest
Balance at Dec. 29, 2018	$ 1,478,342	$ 254	$ 835,828	$ (116,454)	$ (97,924)	$ 856,507	$ 131
Increase (Decrease) in Stockholders' Equity
Net income	36,989					36,989
Other comprehensive loss, net of tax	8,073				8,073
Stock-based compensation	3,966		3,966
Withheld shares on restricted share units for withholding taxes	(94)			(94)
Stock options exercised	2,292		2,292
Repurchases of common stock	(13,555)			(13,555)
Cash dividends paid	(10,625)					(10,625)
Balance at Mar. 30, 2019	1,505,388	254	842,086	(130,103)	(89,851)	882,871	131
Balance at Dec. 29, 2018	1,478,342	254	835,828	(116,454)	(97,924)	856,507	131
Increase (Decrease) in Stockholders' Equity
Net income	116,428
Other comprehensive loss, net of tax	(14,684)
Repurchases of common stock	(95,000)
Balance at Sep. 28, 2019	1,472,212	256	860,871	(216,384)	(112,608)	939,946	131
Balance at Mar. 30, 2019	1,505,388	254	842,086	(130,103)	(89,851)	882,871	131
Increase (Decrease) in Stockholders' Equity
Net income	43,792					43,792
Other comprehensive loss, net of tax	(5,731)				(5,731)
Stock-based compensation	8,284		8,284
Withheld shares on restricted share units for withholding taxes	(4,010)			(4,010)
Stock options exercised	4,823	1	4,822
Repurchases of common stock	(31,955)			(31,955)
Cash dividends paid	(10,649)					(10,649)
Balance at Jun. 29, 2019	1,509,942	255	855,192	(166,068)	(95,582)	916,014	131
Increase (Decrease) in Stockholders' Equity
Net income	35,647					35,647
Other comprehensive loss, net of tax	(17,026)				(17,026)
Stock-based compensation	3,488		3,488
Withheld shares on restricted share units for withholding taxes	(790)			(790)
Stock options exercised	2,192	1	2,191
Repurchases of common stock	(49,526)			(49,526)
Cash dividends paid	(11,715)					(11,715)
Balance at Sep. 28, 2019	1,472,212	256	860,871	(216,384)	(112,608)	939,946	131
Balance at Dec. 28, 2019	1,496,014	256	867,996	(216,447)	(106,823)	950,901	131
Increase (Decrease) in Stockholders' Equity
Net income	24,644					24,644
Other comprehensive loss, net of tax	(14,979)				(14,979)
Stock-based compensation	2,965		2,965
Withheld shares on restricted share units for withholding taxes	(443)			(443)
Stock options exercised	3,399		3,399
Repurchases of common stock	(22,927)			(22,927)
Cash dividends paid	(11,725)					(11,725)
Balance at Mar. 28, 2020	1,476,948	256	874,360	(239,817)	(121,802)	963,820	131
Balance at Dec. 28, 2019	1,496,014	256	867,996	(216,447)	(106,823)	950,901	131
Increase (Decrease) in Stockholders' Equity
Net income	71,009
Other comprehensive loss, net of tax	(415)
Repurchases of common stock	(22,900)
Balance at Sep. 26, 2020	1,529,562	258	891,924	(242,323)	(107,238)	986,810	131
Balance at Mar. 28, 2020	1,476,948	256	874,360	(239,817)	(121,802)	963,820	131
Increase (Decrease) in Stockholders' Equity
Net income	(8,991)					(8,991)
Other comprehensive loss, net of tax	(2,417)				(2,417)
Stock-based compensation	7,887		7,887
Withheld shares on restricted share units for withholding taxes	(2,375)			(2,375)
Stock options exercised	3,060	1	3,059
Cash dividends paid	(11,678)					(11,678)
Balance at Jun. 27, 2020	1,462,434	257	885,306	(242,192)	(124,219)	943,151	131
Increase (Decrease) in Stockholders' Equity
Net income	55,356					55,356
Other comprehensive loss, net of tax	16,981				16,981
Stock-based compensation	3,692		3,692
Withheld shares on restricted share units for withholding taxes	(131)			(131)
Stock options exercised	2,927	1	2,926
Cash dividends paid	(11,697)					(11,697)
Balance at Sep. 26, 2020	$ 1,529,562	$ 258	$ 891,924	$ (242,323)	$ (107,238)	$ 986,810	$ 131

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parentheticals) - $ / shares	3 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019
Statement of Stockholders' Equity [Abstract]
Cash dividends paid, per share (in dollars per share)	$ 0.48	$ 0.48	$ 0.48	$ 0.48	$ 0.43	$ 0.43

Summary of Significant Accounti

Summary of Significant Accounting Policies and Other Information	9 Months Ended
	Sep. 26, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies and Other Information	Summary of Significant Accounting Policies and Other Information Nature of Operations Littelfuse, Inc. and subsidiaries (the “Company”) is a global manufacturer of leading technologies in circuit protection, power control and sensing. Serving over 100,000 end customers, the Company’s products are found in automotive and commercial vehicles, industrial applications, data and telecommunications, medical devices, consumer electronics and appliances. With its broad product portfolio of fuses, semiconductors, polymers, ceramics, relays and sensors, and extensive global infrastructure, the Company’s worldwide associates partner with its customers to design, manufacture and deliver innovative, high-quality solutions for a safer, greener and increasingly connected world. Basis of Presentation The Company’s accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with U.S. Generally Accepted Accounting Principles (“GAAP”) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the consolidated balance sheets, statements of net income and comprehensive income, statements of cash flows, and statement of stockholders' equity prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. They have been prepared in accordance with accounting policies described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 28, 2019 which should be read in conjunction with the disclosures therein. In the opinion of management, all adjustments considered necessary for a fair presentation have been included and are of a normal, recurring nature. Operating results for interim periods are not necessarily indicative of annual operating results. Revenue Recognition Revenue Disaggregation The following tables disaggregate the Company’s revenue by primary business units for the three and nine months ended September 26, 2020 and September 28, 2019: Three Months Ended September 26, 2020 Nine Months Ended September 26, 2020 (in thousands) Electronics Automotive Industrial Electronics Automotive Industrial Electronics – Passive Products and Sensors $ 108,253 $ — $ — $ 108,253 $ 285,697 $ — $ — $ 285,697 Electronics – Semiconductor 147,096 — — 147,096 407,112 — — 407,112 Passenger Car Products — 52,691 — 52,691 — 135,645 — 135,645 Automotive Sensors — 26,093 — 26,093 — 64,166 — 64,166 Commercial Vehicle Products — 25,940 — 25,940 — 71,682 — 71,682 Industrial Products — — 31,493 31,493 — — 80,697 80,697 Total $ 255,349 $ 104,724 $ 31,493 $ 391,566 $ 692,809 $ 271,493 $ 80,697 $ 1,044,999 Three Months Ended September 28, 2019 Nine Months Ended September 28, 2019 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Electronics – Passive Products and Sensors $ 94,766 $ — $ — $ 94,766 $ 311,624 $ — $ — $ 311,624 Electronics – Semiconductor 132,486 — — 132,486 440,575 — — 440,575 Passenger Car Products — 53,889 — 53,889 — 164,348 — 164,348 Automotive Sensors — 23,877 — 23,877 — 74,616 — 74,616 Commercial Vehicle Products — 26,915 — 26,915 — 87,850 — 87,850 Industrial Products — — 30,038 30,038 — — 86,337 86,337 Total $ 227,252 $ 104,681 $ 30,038 $ 361,971 $ 752,199 $ 326,814 $ 86,337 $ 1,165,350 See Note 14, Segment Information for net sales by segment and countries. Revenue Recognition The Company recognizes revenue on product sales in the period in which the Company satisfies its performance obligation and control of the product is transferred to the customer. The Company’s sales arrangements with customers are predominately short term in nature and generally provide for transfer of control at the time of shipment as this is the point at which title and risk of loss of the product transfers to the customer. At the end of each period, for those shipments where title to the products and the risk of loss and rewards of ownership do not transfer until the product has been received by the customer, the Company adjusts revenues and cost of sales for the delay between the time that the products are shipped and when they are received by the customer. The amount of revenue recorded reflects the consideration to which the Company expects to be entitled in exchange for goods and may include adjustments for customer allowance, rebates and price adjustments. The Company’s distribution channels are primarily through direct sales and independent third-party distributors. The Company elected the practical expedient under Accounting Standards Codification ("ASC") 340-40-25-4 to expense commissions when incurred as the amortization period of the commission asset the Company would have otherwise recognized is less than one year. Revenue and Billing The Company generally accepts orders from customers through receipt of purchase orders or electronic data interchange based on written sales agreements and purchasing contracts. Contract pricing and selling agreement terms are based on market factors, costs, and competition. Pricing is often negotiated as an adjustment (premium or discount) from the Company’s published price lists. The customer is invoiced when the Company’s products are shipped to them in accordance with the terms of the sales agreement. As the Company’s standard payment terms are less than one year, the Company elected the practical expedient under ASC 606-10-32-18 to not assess whether a contract has a significant financing component. The Company also elected the practical expedient provided in ASC 606-10-25-18B to treat all product shipping and handling activities as fulfillment activities, and therefore recognize the gross revenue associated with the contract, inclusive of any shipping and handling revenue. Ship and Debit Program Some of the terms of the Company’s sales agreements and normal business conditions provide customers (distributors) the ability to receive price adjustments on products previously shipped and invoiced. This practice is common in the industry and is referred to as a “ship and debit” program. This program allows the distributor to debit the Company for the difference between the distributors’ contracted price and a lower price for specific transactions. Under certain circumstances (usually in a competitive situation or large volume opportunity), a distributor will request authorization for pricing allowances to reduce its price. When the Company approves such a reduction, the distributor is authorized to “debit” its account for the difference between the contracted price and the lower approved price. The Company establishes reserves for this program based on historic activity, electronic distributor inventory levels and actual authorizations for the debit and recognizes these debits as a reduction of revenue. Return to Stock The Company has a return to stock policy whereby certain customers, with prior authorization from Littelfuse management, can return previously purchased goods for full or partial credit. The Company establishes an estimated allowance for these returns based on historic activity. Sales revenue and cost of sales are reduced to anticipate estimated returns. Volume Rebates The Company offers volume based sales incentives to certain customers to encourage greater product sales. If customers achieve their specific quarterly or annual sales targets, they are entitled to rebates. The Company estimates the projected amount of rebates that will be achieved by the customer and recognizes this estimated cost as a reduction to revenue as products are sold. Recently Adopted Accounting Standards In June 2016, the FASB issued ASU No. 2016-13, "Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments." The standard modifies the measurement approach for credit losses on financial instruments, including trade receivables, from an incurred loss method to a current expected credit loss method ("CECL"). The standard requires the measurement of expected credit losses to be based on relevant information, including historical experiences, current conditions and a forecast that is supportable. The Company adopted the new standard on December 29, 2019. The adoption of the standard did not have a material effect on our Condensed Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-13 "Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirement for Fair Value Measurement." ASU 2018-13 modifies the disclosure requirements in Topic 820: "Fair Value Measurement," based on the FASB Concepts Statement, "Conceptual Framework for Financial Reporting - Chapter 8: Notes to Financial Statements," including consideration of costs and benefits. The new standard removes certain disclosures, modifies other disclosures and adds additional disclosures related to fair value measurement. The Company adopted the new standard on December 29, 2019. The adoption of ASU 2018-13 did not have a material impact on our Condensed Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic: 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)." ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The Company adopted the new standard on December 29, 2019. The adoption of ASU 2018-15 did not have a material impact on our Condensed Consolidated Financial Statements. In March 2020, the FASB issued ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” This ASU provides optional expedient and exceptions for applying generally accepted accounting principles to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The objective of this is to provide optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting due to the cessation of the London Interbank Offered Rate (LIBOR). The amendments in this update are effective for all entities as of March 12, 2020 through December 31, 2022. The Company does not expect a material effect from the adoption of this guidance on its Condensed Consolidated Financial Statements.

Inventories

Inventories	9 Months Ended
	Sep. 26, 2020
Inventory Disclosure [Abstract]
Inventories	Inventories The components of inventories at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Raw materials $ 81,849 $ 76,732 Work in process 90,494 84,561 Finished goods 105,425 110,388 Inventory Reserves (33,936) (34,174) Total $ 243,832 $ 237,507

Property, Plant, and Equipment

Property, Plant, and Equipment	9 Months Ended
	Sep. 26, 2020
Property, Plant and Equipment [Abstract]
Property, Plant, and Equipment	Property, Plant, and Equipment The components of net property, plant, and equipment at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Land $ 23,438 $ 24,758 Building 122,914 108,501 Equipment 656,681 631,273 Accumulated depreciation and amortization (463,163) (419,915) Total $ 339,870 $ 344,617 The Company recorded depreciation expense of $14.2 million and $13.3 million for the three months ended September 26, 2020 and September 28, 2019, respectively, and $42.0 million and $39.0 million for nine months ended September 26, 2020 and September 28, 2019, respectively.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 26, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets The amounts for goodwill and changes in the carrying value by segment for the nine months ended September 26, 2020 are as follows: (in thousands) Electronics Automotive Industrial Total As of December 28, 2019 $ 650,796 $ 131,321 $ 38,472 $ 820,589 Impairments — (33,841) — (33,841) Currency translation 11,122 1,988 (67) 13,043 As of September 26, 2020 $ 661,918 $ 99,468 $ 38,405 $ 799,791 The Company tests its goodwill annually for impairment on the first day of its fiscal fourth quarter, or more frequently if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. During the second quarter of 2020, the Company recorded a non-cash charge of $33.8 million to recognize the impairment of goodwill in the automotive sensors reporting unit within the Automotive segment. The goo dwill impairment charge was due to reductions in the estimated fair value for the automotive sensors reporting unit based on lower expectations for future revenue, profitability and cash flows as compared to the expectations of the 2019 annual goodwill impairment test. These lower future expectations were driven by projected extended declines in end market demand due to the COVID-19 pandemic. In addition, during the second quarter of 2020, certain customers notified the Company of their decision to delay future programs along with a customer canceling their existing program. The goodwill impairment charge was determined using Level 3 inputs, including discounted cash flow analysis and comparable marketplace fair value data. As of September 26, 2020 , the automotive sensors reporting unit had $9.4 million of remaining goodwill. The components of other intangible assets as of September 26, 2020 and December 28, 2019 are as follows: As of September 26, 2020 (in thousands) Gross Accumulated Amortization Net Book Value Land use rights $ 9,913 $ 1,895 $ 8,018 Patents, licenses and software 133,737 $ 88,142 $ 45,595 Distribution network 43,547 38,107 5,440 Customer relationships, trademarks, and tradenames 365,300 128,194 237,106 Total $ 552,497 $ 256,338 $ 296,159 As of December 28, 2019 (in thousands) Gross Accumulated Amortization Net Book Value Land use rights $ 9,649 $ 1,730 $ 7,919 Patents, licenses and software 131,164 78,828 52,336 Distribution network 43,239 36,163 7,076 Customer relationships, trademarks, and tradenames 360,534 106,618 253,916 Total $ 544,586 $ 223,339 $ 321,247 During the three months ended September 26, 2020 and September 28, 2019, the Company recorded amortization expense of $10.1 million and $9.8 million, respectively. During the nine months ended September 26, 2020 and September 28, 2019, the Company recorded amortization expense of $29.9 million and $30.1 million, respectively. The Company recognized a $0.3 million non-cash impairment charge in the first quarter of 2020 on a certain patent triggered by the Company’s announcement to consolidate a manufacturing facility within the Industrial segment. Estimated annual amortization expense related to intangible assets with definite lives as of September 26, 2020 is as follows: (in thousands) Amount 2020 $ 41,742 2021 38,258 2022 37,274 2023 32,492 2024 29,695 2025 and thereafter 146,610 Total $ 326,071

Accrued Liabilities

Accrued Liabilities	9 Months Ended
	Sep. 26, 2020
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities The components of accrued liabilities as of September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Employee-related liabilities $ 49,805 $ 40,774 Operating lease liability 6,866 7,259 Interest 2,747 5,058 Professional services 2,869 3,986 Restructuring liability 4,542 2,679 Other non-income taxes 3,509 1,940 Other 28,099 22,424 Total $ 98,437 $ 84,120 Employee-related liabilities consist primarily of payroll, sales commissions, bonus, employee benefit accruals and workers’ compensation. Bonus accruals include amounts earned pursuant to the Company’s primary employee incentive compensation plans. Other accrued liabilities include miscellaneous operating accruals and other client-related liabilities.

Restructuring, Impairment and O

Restructuring, Impairment and Other Charges	9 Months Ended
	Sep. 26, 2020
Restructuring and Related Activities [Abstract]
Restructuring, Impairment and Other Charges	Restructuring, Impairment and Other Charges The Company recorded restructuring, impairment and other charges for the three and nine months ended September 26, 2020 and September 28, 2019 as follows: Three months ended September 26, 2020 Nine months ended September 26, 2020 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Employee terminations $ 388 $ 162 $ 648 $ 1,198 $ 2,125 $ 770 $ 1,719 $ 4,614 Other restructuring charges — — 79 79 — 108 104 212 Total restructuring charges 388 162 727 1,277 2,125 878 1,823 4,826 Impairment — — — — — 33,841 2,237 36,078 Total $ 388 $ 162 $ 727 $ 1,277 $ 2,125 $ 34,719 $ 4,060 $ 40,904 Three months ended September 28, 2019 Nine months ended September 28, 2019 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Employee terminations $ 655 $ 109 $ 49 $ 813 $ 4,153 $ 3,955 $ 770 $ 8,878 Other restructuring charges 128 1,150 124 1,402 141 1,240 374 1,755 Total restructuring charges 783 1,259 173 2,215 4,294 5,195 1,144 10,633 Impairment — 322 — 322 — 322 — 322 Total $ 783 $ 1,581 $ 173 $ 2,537 $ 4,294 $ 5,517 $ 1,144 $ 10,955 2020 For the three and nine months ended September 26, 2020, the Company recorded total restructuring charges of $1.3 million and $4.8 million, primarily for employee termination costs. These charges primarily related to the reorganization of certain manufacturing, selling and administrative functions across all segments and the previously announced consolidation of a manufacturing facility within the Industrial segment. The Company also recognized $36.1 million of impairment charges for the nine months ended September 26, 2020, which included a $33.8 million goodwill impairment charge associated with the automotive sensors reporting unit within the Automotive segment in the second quarter of 2020 and a $2.2 million impairment charge related to the land and building associated with the Company’s previously announced consolidation of a manufacturing facility within the Industrial segment in the first quarter of 2020. The impairment charges of the land and building were included in selling, general and administrative expenses. See Note 4, Goodwill and Other Intangible Assets for further discussion regarding the goodwill impairment charge. 2019 For the three and nine months ended September 28, 2019, the Company recorded total restructuring charges of $2.2 million, and $10.6 million, respectively, for employee termination costs and other restructuring charges. These charges primarily related to reorganization of operations and selling, general and administrative functions as well as integration of IXYS within the Electronics segment and the reorganization of operations in the commercial vehicle products and automotive sensors businesses within the Automotive segment. The restructuring liability as of September 26, 2020 and December 28, 2019 are $4.5 million and $2.7 million, respectively. The restructuring liability is included within accrued liabilities in the Condensed Consolidated Balance Sheets. The Company anticipates the remaining payments associated with employee terminations will primarily be completed by September 2021.

Debt

Debt	9 Months Ended
	Sep. 26, 2020
Debt Disclosure [Abstract]
Debt	Debt The carrying amounts of debt at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, December 28, Revolving Credit Facility $ 180,000 $ — Term Loan — 145,000 Euro Senior Notes, Series A due 2023 136,417 129,808 Euro Senior Notes, Series B due 2028 110,766 105,400 U.S. Senior Notes, Series A due 2022 25,000 25,000 U.S. Senior Notes, Series B due 2027 100,000 100,000 U.S. Senior Notes, Series A due 2025 50,000 50,000 U.S. Senior Notes, Series B due 2030 125,000 125,000 Other 2,619 2,619 Unamortized debt issuance costs (4,295) (3,669) Total debt 725,507 679,158 Less: Current maturities — (10,000) Total long-term debt $ 725,507 $ 669,158 Revolving Credit Facility / Term Loan On March 4, 2016, the Company entered into a five-year credit agreement (“Credit Agreement”) with a group of lenders for up to $700.0 million. The Credit Agreement consisted of an unsecured revolving credit facility (“Revolving Credit Facility”) of $575.0 million and an unsecured term loan credit facility (“Term Loan”) of up to $125.0 million. In addition, the Company had the ability, from time to time, to increase the size of the Revolving Credit Facility and the Term Loan by up to an additional $150.0 million, in the aggregate, in each case in minimum increments of $25.0 million, subject to certain conditions and the agreement of participating lenders. On October 13, 2017, the Company amended the Credit Agreement to increase the Revolving Credit Facility from $575.0 million to $700.0 million and increase the Term Loan from $125.0 million to $200.0 million and to extend the expiration date from March 4, 2021 to October 13, 2022. The Credit Agreement also included the option for the Company to increase the size of the Revolving Credit Facility and the Term Loan by up to an additional $300.0 million, in the aggregate, subject to the satisfaction of certain conditions set forth in the Credit Agreement. Term Loans could be made in up to two advances. The first advance of $125.0 million occurred on October 13, 2017 and the second advance of $75.0 million occurred on January 16, 2018. For the Term Loan, the Company was required to make quarterly principal payments of 1.25% of the original term loan ($2.5 million quarterly) through maturity, with the remaining balance due on October 13, 2022. The Company paid $5.0 million of principal payments on the term loan before the Company amended the Credit Agreement on April 3, 2020 as discussed below. On March 25, 2020, the company borrowed $100.0 million from the revolving credit facility to preserve financial flexibility and enhance liquidity, given the increasing levels of uncertainty related to coronavirus disease 2019 ("COVID-19"). On April 3, 2020, the Company amended the Credit Agreement to effect certain changes, including, among others: (i) eliminating the $200.0 million unsecured term loan credit facility, the remaining outstanding balance ($140.0 million) of which was repaid in full on April 3, 2020 through the revolving credit facility; (ii) making certain financial and non-financial covenants less restrictive on the Company; (iii) modifying performance-based interest rate margins and undrawn fees; and (iv) extending the maturity date to April 3, 2025. The amended Credit Agreement also allows the Company to increase the size of the revolving credit facility or enter into one or more tranches of term loans if there is no event of default and the Company is in compliance with certain financial covenants. The Company made payments of $60.0 million on the amended revolving credit facility during the three months ended September 26, 2020. The balance under the facility was $180.0 million as of September 26, 2020. Outstanding borrowings under the amended Credit Agreement bears interest, at the Company’s option, at either LIBOR, fixed for interest periods of one, two, three or six-month periods, plus 1.25% to 2.00%, or at the bank’s Base Rate, as defined, plus 0.25% to 1.00%, based upon the Company’s Consolidated Leverage Ratio, as defined. The Company was also required to pay commitment fees on unused portions of the credit agreement ranging from 0.125% to 0.20%, based on the Consolidated Leverage Ratio, as defined in the agreement. The amended Credit Agreement included representations, covenants and events of default that are customary for financing transactions of this nature. The effective interest rate on outstanding borrowings under the credit facility was 1.90% at September 26, 2020. As of September 26, 2020, the Company had no amount outstanding in letters of credit and had available $245.1 million of borrowing capacity under the Revolving Credit Facility based on financial covenants. At September 26, 2020, the Company was in compliance with all covenants under the Credit Agreement. Senior Notes On December 8, 2016, the Company entered into a Note Purchase Agreement, pursuant to which the Company issued and sold €212 million aggregate principal amount of senior notes in two series. The funding date for the Euro denominated senior notes occurred on December 8, 2016 for €117 million in aggregate amount of 1.14% Senior Notes, Series A, due December 8, 2023 (“Euro Senior Notes, Series A due 2023”), and €95 million in aggregate amount of 1.83% Senior Notes, Series B due December 8, 2028 (“Euro Senior Notes, Series B due 2028”) (together, the “Euro Senior Notes”). Interest on the Euro Senior Notes is payable semiannually on June 8 and December 8, commencing June 8, 2017. On December 8, 2016, the Company entered into a Note Purchase Agreement, pursuant to which the Company issued and sold $125 million aggregate principal amount of senior notes in two series. On February 15, 2017, $25 million in aggregate principal amount of 3.03% Senior Notes, Series A, due February 15, 2022 (“U.S. Senior Notes, Series A due 2022”), and $100 million in aggregate principal amount of 3.74% Senior Notes, Series B, due February 15, 2027 (“U.S. Senior Notes, Series B due 2027”) (together, the “U.S. Senior Notes due 2022 and 2027”) were funded. Interest on the U.S. Senior Notes due 2022 and 2027 is payable semiannually on February 15 and August 15, commencing August 15, 2017. On November 15, 2017, the Company entered into a Note Purchase Agreement pursuant to which the Company issued and sold $175 million in aggregate principal amount of senior notes in two series. On January 16, 2018, $50 million aggregate principal amount of 3.48% Senior Notes, Series A, due February 15, 2025 (“U.S. Senior Notes, Series A due 2025”) and $125 million in aggregate principal amount of 3.78% Senior Notes, Series B, due February 15, 2030 (“U.S. Senior Notes, Series B due 2030”) (together the “U.S. Senior Notes due 2025 and 2030” and with the Euro Senior Notes and the U.S. Senior Notes due 2022 and 2027, the “Senior Notes”) were funded. Interest on the U.S. Senior Notes due 2025 and 2030 is payable semiannually on February 15 and August 15, commencing on August 15, 2018. The Senior Notes have not been registered under the Securities Act, or applicable state securities laws. The Senior Notes are general unsecured senior obligations and rank equal in right of payment with all existing and future unsecured unsubordinated indebtedness of the Company. The Senior Notes are subject to certain customary covenants, including limitations on the Company’s ability, with certain exceptions, to engage in mergers, consolidations, asset sales and transactions with affiliates, to engage in any business that would substantially change the general business of the Company, and to incur liens. In addition, the Company is required to satisfy certain financial covenants and tests relating to, among other matters, interest coverage and leverage. At September 26, 2020, the Company was in compliance with all covenants under the Senior Notes. The Company may redeem the Senior Notes upon the satisfaction of certain conditions and the payment of a make-whole amount to noteholders and are required to offer to repurchase the Senior Notes at par following certain events, including a change of control. Interest paid on all Company debt was $6.4 million for the three months ended September 26, 2020 and September 28, 2019, and $17.2 million and $17.9 million for the nine months ended September 26, 2020 and September 28, 2019, respectively.

Fair Value of Assets and Liabil

Fair Value of Assets and Liabilities	9 Months Ended
	Sep. 26, 2020
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	Fair Value of Assets and Liabilities For assets and liabilities measured at fair value on a recurring and nonrecurring basis, a three-level hierarchy of measurements based upon observable and unobservable inputs is used to arrive at fair value. Observable inputs are developed based on market data obtained from independent sources, while unobservable inputs reflect the Company’s assumptions about valuation based on the best information available in the circumstances. Depending on the inputs, the Company classifies each fair value measurement as follows: Level 1 —Valuations based on unadjusted quoted prices for identical assets or liabilities in active markets; Level 2 —Valuations based upon quoted prices for similar instruments, prices for identical or similar instruments in markets that are not active, or model-derived valuations, all of whose significant inputs are observable, and Level 3 —Valuations based upon one or more significant unobservable inputs. Following is a description of the valuation methodologies used for instruments measured at fair value and their classification in the valuation hierarchy. Cash Equivalents Cash equivalents primarily consist of money market funds, which are held with an institution with sound credit rating and are highly liquid. The Company classified cash equivalents as Level 1 and are valued at cost which approximates fair value. Investments in Equity Securities Investments in equity securities listed on a national market or exchange are valued at the last sales price and classified within Level 1 of the valuation hierarchy and recorded in investments and other assets. The Company has certain convertible debt and convertible preferred stock investments that are accounted for under the cost method reflected in other assets in the Condensed Consolidated Balance Sheets. During the three months ended September 26, 2020, the Company recorded impairment charges of $0.1 million and during the nine months ended September 28, 2019, the Company recorded impairment charges of $2.8 million in Other income, net in the Condensed Consolidated Statements of Net Income to adjust these certain investments to their estimated fair value. As of September 26, 2020 and December 28, 2019, the balances of these investments were $0.5 million and $0.4 million, respectively. The fair value of these investments are measured on a nonrecurring basis using Level 3 inputs under the fair value hierarchy. The Company's accounting and finance management determines the valuation policies and procedures for Level 3 fair value measurements and is responsible for the development and determination of unobservable inputs. Mutual Funds The Company has a non-qualified Supplemental Retirement and Savings Plan which provides additional retirement benefits for certain management employees and named executive officers by allowing participants to defer a portion of their annual compensation. The Company maintains accounts for participants through which participants make investment elections. The marketable securities are classified as Level 1 under the fair value hierarchy as they are maintained in mutual funds with readily determinable fair value and recorded in other assets. There were no changes during the quarter ended September 26, 2020 to the Company’s valuation techniques used to measure asset and liability fair values on a recurring basis. On October 30, 2019, the Company entered a foreign currency exchange forward contract to mitigate the currency fluctuation risk between the Chinese renminbi and U.S. dollar. The foreign currency contract was not designated as a hedge instrument and was marked to market on a monthly basis. The notional value of the forward contracts at December 28, 2019 was $16.0 million and expired on May 5, 2020. On March 23, 2020, the Company unwound the foreign currency exchange forward contract entered on October 30, 2019 and recognized a gain of $0.2 million within Other income, net during the nine months ended September 26, 2020 . The fair value of the foreign currency forward contract was valued using market exchange rates and classified as a Level 2 input under the fair value hierarchy. As of September 26, 2020 and December 28, 2019, the Company did not hold any non-financial assets or liabilities that are required to be measured at fair value on a recurring basis. The following table presents assets measured at fair value by classification within the fair value hierarchy as of September 26, 2020: Fair Value Measurements Using (in thousands) Quoted Prices in Significant Significant Total Cash Equivalents $ 92,472 $ — $ — $ 92,472 Investments in equity securities 15,042 — — 15,042 Mutual funds 11,692 — — 11,692 The following table presents assets measured at fair value by classification within the fair value hierarchy as of December 28, 2019: Fair Value Measurements Using (in thousands) Quoted Prices in Significant Significant Total Cash Equivalents $ 118,999 $ — $ — $ 118,999 Investments in equity securities 12,969 — — 12,969 Mutual funds 10,464 — — 10,464 In addition to the methods and assumptions used for the financial instruments recorded at fair value as discussed above, the following methods and assumptions are used to estimate the fair value of other financial instruments that are not marked to market on a recurring basis. The Company’s other financial instruments include cash and cash equivalents, short-term investments, accounts receivable and its long-term debt. Due to their short-term maturity, the carrying amounts of cash and cash equivalents, short-term investments and accounts receivable approximate their fair values. The Company’s revolving and term loan debt facilities’ fair values approximate book value at September 26, 2020 and December 28, 2019, as the rates on these borrowings are variable in nature. The carrying value and estimated fair values of the Company’s Euro Senior Notes, Series A and Series B and USD Senior Notes, Series A and Series B, as of September 26, 2020 and December 28, 2019 were as follows: September 26, 2020 December 28, 2019 (in thousands) Carrying Estimated Carrying Estimated Euro Senior Notes, Series A due 2023 $ 136,417 $ 136,686 $ 129,808 $ 131,710 Euro Senior Notes, Series B due 2028 110,766 114,947 105,400 110,336 USD Senior Notes, Series A due 2022 25,000 25,460 25,000 25,054 USD Senior Notes, Series B due 2027 100,000 109,367 100,000 102,548 USD Senior Notes, Series A due 2025 50,000 53,323 50,000 50,775 USD Senior Notes, Series B due 2030 125,000 138,340 125,000 127,701 The Company recognized impairment charges of $1.9 million for the land and building and $0.3 million for a certain patent as a result of the Company’s announcement to consolidate a manufacturing facility within the Industrial segment during the first quarter of 2020. See Note 6, Restructuring, Impairment and Other Charges, for further discussion. The fair value of the land and building was valued using a real estate appraisal and classified as a Level 3 input under the fair value hierarchy. The second quarter of 2020 goodwill impairment charge was the result of measuring a reporting unit at fair value on a nonrecurring basis as shown below: Nine Months Ended September 26, 2020 September 26, 2020 (in thousands) Impairment Charge Estimated Fair Value Measurement (Level 3) Carrying Value Goodwill $33,841 $8,953 $ 9,449 See Note 4, Goodwill and Other Intangible Assets for further discussion regarding goodwill impairment charges.

Benefit Plans

Benefit Plans	9 Months Ended
	Sep. 26, 2020
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans The Company has company-sponsored defined benefit pension plans covering employees in the U.K., Germany, the Philippines, China, Japan, Mexico, Italy and France. The amount of the retirement benefits provided under the plans is based on years of service and final average pay. The Company recognizes interest cost, expected return on plan assets, and amortization of prior service, net within Other income,, net in the Condensed Consolidated Statements of Net Income. The components of net periodic benefit cost for the three and nine months ended September 26, 2020 and September 28, 2019 were as follows: For the Three Months Ended For the Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Components of net periodic benefit cost: Service cost $ 615 $ 509 $ 1,825 $ 1,523 Interest cost 511 777 1,655 2,374 Expected return on plan assets (422) (773) (1,551) (2,384) Amortization of prior service and net actuarial loss 279 60 688 184 Net periodic benefit cost $ 983 $ 573 $ 2,617 $ 1,697 The Company expects to make approximately $2.3 million of cash contributions to its pension plans in 2020. The Company also sponsors certain post-employment plans in foreign countries and other statutory benefit plans. The Company recorded $0.5 million and $0.2 million expense for the three months ended September 26, 2020 and September 28, 2019 , respectively, and $1.5 million and $0.6 million expense for the nine months ended September 26, 2020 and September 28, 2019, respectively, in Cost of Sales and Other income, net within the Condensed Consolidated Statements of Net Income. For three and nine months ended September 26, 2020, the pre-tax amounts recognized in other comprehensive income (loss) as components of net periodic benefit costs for these plans were $0.2 million and $0.5 million. On April 7, 2020, the Company entered into a definitive agreement to purchase a group annuity contract, under which an insurance company will be required to pay and administer pension payments to certain of the Company’s U.K. pension plan participants, or their designated beneficiaries, who have been receiving pension payments. The purchase of this group annuity contract will reduce the Company’s outstanding pension benefit obligation by approximately $36 million, representing approximately 30% of the total obligations of the Company’s qualified pension plans, and will be funded with pension plan assets and additional cash on hand. In connection with this transaction, the Company will record a one-time non-cash settlement charge in the second half of 2021 currently estimated between $18 million and $22 million, reflecting the accelerated recognition of unamortized actuarial losses in the plan. The actual settlement charge could differ from this estimate due to final data and plan wind-up expenses. Due to the signing of the group annuity contract being a significant change in the U.K. pension plan, the liabilities of the plan were remeasured as of April 6, 2020 resulting in an increase of $13.4 million (£10.9 million) to both the net pension liability and unamortized actuarial loss within other comprehensive income (loss) during the second quarter. Additionally, the Company made a cash contribution of $10.4 million (£8.4 million) under this agreement during the second quarter.

Other Comprehensive Income

Other Comprehensive Income	9 Months Ended
	Sep. 26, 2020
Equity [Abstract]
Other Comprehensive Income	Other Comprehensive Income Changes in other comprehensive income (loss) by component were as follows: (in thousands) Three Months Ended Three Months Ended Pre-tax Tax Net of Tax Pre-tax Tax Net of Tax Defined benefit pension plan and other adjustments $ 273 $ (290) $ 563 $ 155 $ 18 $ 137 Foreign currency translation adjustments 16,418 — 16,418 (17,163) — (17,163) Total change in other comprehensive income (loss) $ 16,691 $ (290) $ 16,981 $ (17,008) $ 18 $ (17,026) (in thousands) Nine Months Ended September 26, 2020 Nine Months Ended September 28, 2019 Pre-tax Tax Net of Tax Pre-tax Tax Net of Tax Defined benefit pension plan and other adjustments $ (12,270) $ (2,555) $ (9,715) $ 278 $ 29 $ 249 Foreign currency translation adjustments 9,300 — 9,300 (14,933) — (14,933) Total change in other comprehensive loss $ (2,970) $ (2,555) $ (415) $ (14,655) $ 29 $ (14,684) Due to the signing of the group annuity contract being a significant change in the U.K. pension plan, the liabilities of the plan were remeasured as of April 6, 2020 resulting in an increase of $13.4 million to unamortized actuarial loss within other comprehensive income (loss). See Note 9, Benefits Plans for further discussion. The following tables set forth the changes in accumulated other comprehensive income (loss) by component for the nine months ended September 26, 2020 and September 28, 2019: (in thousands) Pension and Foreign Accumulated Balance at December 28, 2019 $ (18,046) $ (88,777) $ (106,823) Activity in the period (9,715) 9,300 (415) Balance at September 26, 2020 $ (27,761) $ (79,477) $ (107,238) (in thousands) Pension and Foreign Accumulated Balance at December 29, 2018 $ (9,959) $ (87,965) $ (97,924) Activity in the period 249 (14,933) (14,684) Balance at September 28, 2019 $ (9,710) $ (102,898) $ (112,608) Amounts reclassified from accumulated other comprehensive income (loss) to earnings for the three and nine months ended September 26, 2020 and September 28, 2019 were as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Pension and Postemployment plans: Amortization of prior service and net actuarial loss $ 452 $ 60 $ 1,226 $ 184 The Company recognizes the amortization of prior service costs in Other income, net within the Condensed Consolidated Statements of Net Income.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 26, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rate for the three and nine months ended September 26, 2020 was 17.9% and 23.1% respectively, compared to the effective tax rate for the three and nine months ended September 28, 2019 of 13.9% and 17.7%. The effective tax rates for the 2020 periods are higher than the effective tax rates for the comparable 2019 periods, primarily due to the impact of the goodwill impairment charge of $33.8 million that was recorded in the second quarter of 2020, the substantial majority of which did not result in a tax benefit in the annual estimated effective tax rate, as well as a reduction in the forecasted income earned in lower tax jurisdictions in 2020 driven by the uncertainty resulting from the impact of COVID-19. The effective tax rate for the first nine months of 2020 is higher than the applicable U.S. statutory tax rate primarily due to the impact of the goodwill impairment charge of $33.8 million that was recorded in the second quarter of 2020, the substantial majority of which did not result in a tax benefit in the annual estimated effective tax rate, as well as the forecasted impact of non-U.S. losses and expenses with no tax benefit and the U.S. global intangible low-taxed income tax provisions (in the 2019 comparable period the impact of these items was more than offset by the impact of income earned in lower tax jurisdictions), offset in part by the impact of income earned in lower tax jurisdictions.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 26, 2020
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the computation of basic and diluted earnings per share: Three Months Ended Nine Months Ended (in thousands, except per share amounts) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Numerator: Net income as reported $ 55,356 $ 35,647 $ 71,009 $ 116,428 Denominator: Weighted average shares outstanding Basic 24,357 24,482 24,354 24,646 Effect of dilutive securities 216 202 181 248 Diluted 24,573 24,684 24,535 24,894 Earnings Per Share: Basic earnings per share $ 2.27 $ 1.46 $ 2.92 $ 4.72 Diluted earnings per share $ 2.25 $ 1.44 $ 2.89 $ 4.68 Potential shares of common stock relating to stock options and restricted share units excluded from the earnings per share calculation because their effect would be anti-dilutive were 290,262 and 205,516 for the three months ended September 26, 2020 and September 28, 2019, respectively, and 194,857 and 147,090 for the nine months ended September 26, 2020 and September 28, 2019, respectively. Share Repurchase Program The Company’s Board of Directors authorized the repurchase of up to 1,000,000 shares of the Company’s common stock under a program for the period May 1, 2018 to April 30, 2019 ("2018 program"). On April 26, 2019, the Company's Board of Directors authorized to a program to repurchase up to 1,000,000 shares of the Company's common stock for the period May 1, 2019 to April 30, 2020 ("2019 program") to replace its previous expired 2018 program. On April 23, 2020, the Company's Board of Directors authorized a new program to repurchase up to 1,000,000 shares of the Company's common stock for the period May 1, 2020 to April 30, 2021 (the "2020 program") to replace its previous expired 2019 program. The Company has suspended share repurchases for the near-term due to the uncertainty of the impact and duration of COVID-19 and to focus on other capital allocation priorities.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 26, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions As a result of the Company’s acquisition of IXYS, the Company has equity ownership in various investments that are accounted for under the equity method. The following is a description of the investments and related party transactions. Powersem GmbH: The Company owns 45% of the outstanding equity of Powersem GmbH (“Powersem”), a module manufacturer based in Germany. EB-Tech Co., Ltd.: The Company owns approximately 19% of the outstanding equity of EB Tech Co., Ltd. (“EB Tech”), a company with expertise in radiation technology based in South Korea. Automated Technology (Phil), Inc. : The Company owns approximately 24% of the outstanding common shares of Automated Technology (Phil), Inc. (“ATEC”), a supplier located in the Philippines that provides assembly and test services. One member of the Company's Board of Directors serves on the Board of Directors of ATEC. For the Three Months Ended September 26, 2020 For the Three Months Ended September 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Sales to related party $ 0.4 $ — $ — $ 0.2 $ — $ — Purchase material/service from related party 0.8 — 2.4 0.8 0.1 1.7 For the Nine Months Ended September 26, 2020 For the Nine Months Ended September 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Sales to related party $ 1.1 $ — $ — $ 0.4 $ — $ — Purchase material/service from related party 1.8 — 5.8 2.4 0.3 5.5 September 26, 2020 December 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Accounts Receivable balance $ 0.1 $ — $ — $ — $ — $ — Accounts Payable balance 0.1 — 0.1 0.2 — 0.1 Additionally, the Company has certain cost method investments in VTOOL Ltd. and Securepush Ltd. with a total book value of $0.5 million as of September 26, 2020 and one member of the Company’s Board of Directors is currently an investor and a director of VTOOL Ltd. and Securepush Ltd. On April 26, 2019, the Company sold its subsidiary Microwave Technology, LLC. (“MWT”) resulting in a loss on disposal of $2.6 million reflected in Other income, net in the Condensed Consolidated Statements of Net Income. The operations of MWT were included in the Electronics segment. One member of the Company’s Board of Directors is an owner of a company that purchased MWT.

Segment Information

Segment Information	9 Months Ended
	Sep. 26, 2020
Segment Reporting [Abstract]
Segment Information	Segment Information The Company and its subsidiaries design, manufacture and sell components and modules for circuit protection, power control and sensing throughout the world. The Company reports its operations by the following segments: Electronics, Automotive, and Industrial. An operating segment is defined as a component of an enterprise that engages in business activities from which it may earn revenues and incur expenses, and about which separate financial information is regularly evaluated by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources. The CODM is the Company’s President and Chief Executive Officer (“CEO”). The CODM allocates resources to and assesses the performance of each operating segment using information about its revenue and operating income (loss) before interest and taxes, but does not evaluate the operating segments using discrete balance sheet information. Sales, marketing, and research and development expenses are charged directly into each operating segment. Purchasing, logistics, customer service, finance, information technology, and human resources are shared functions that are allocated back to the three operating segments. The Company does not report inter-segment revenue because the operating segments do not record it. Certain expenses, determined by the CODM to be strategic in nature and not directly related to segments' current results, are not allocated but identified as “Other”. Additionally, the Company does not allocate interest and other income, interest expense, or taxes to operating segments. These costs are not allocated to the segments, as management excludes such costs when assessing the performance of the segments. Although the CODM uses operating income (loss) to evaluate the segments, operating costs included in one segment may benefit other segments. Except as discussed above, the accounting policies for segment reporting are the same as for the Company as a whole. • Electronics Segment : Consists of one of the broadest product offerings in the industry, including fuses and fuse accessories, positive temperature coefficient (“PTC”) resettable fuses, polymer electrostatic discharge (“ESD”) suppressors, varistors, reed switch based magnetic sensing, gas discharge tubes; semiconductor products such as discrete transient voltage suppressor (“TVS”) diodes, TVS diode arrays, protection and switching thyristors, metal-oxide-semiconductor field effect transistors (“MOSFETs”) and silicon carbide diodes; and insulated gate bipolar transistors (“IGBT”) technologies. The segment covers a broad range of end markets, including industrial and automotive electronics, electric vehicle and related infrastructure, data and telecommunications, medical devices, alternative energy, consumer electronics and white goods. • Automotive Segment: Consists of a wide range of circuit protection, power control and sensing technologies for global original equipment manufacturers (“OEMs”), Tier-I suppliers and parts distributors in passenger car, heavy duty truck, off-road vehicles, material handling, agricultural, construction and other commercial vehicle end markets. Passenger car fuse products include fuses and fuse accessories for internal combustion engine vehicles and hybrid and electric vehicles including blade fuses, battery cable protectors, resettable fuses, high-current fuses, and high-voltage fuses. Commercial vehicle products include fuses, switches, relays, and power distribution modules for the commercial vehicle industry. Automotive sensor products include a wide range of automotive and commercial vehicle products designed to monitor the passenger compartment occupants, safety and environment as well as the vehicle’s powertrain. • Industrial Segment: Consists of power fuses, protection relays and controls and other circuit protection products for use in various industrial applications such as oil, gas, mining, alternative energy, electric vehicle infrastructure, non-residential construction, HVAC systems, elevators and other industrial equipment. Segment information is summarized as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Net sales Electronics $ 255,349 $ 227,252 $ 692,809 $ 752,199 Automotive 104,724 104,681 271,493 326,814 Industrial 31,493 30,038 80,697 86,337 Total net sales $ 391,566 $ 361,971 $ 1,044,999 $ 1,165,350 Depreciation and amortization Electronics $ 15,819 $ 14,960 $ 46,967 45,031 Automotive 7,370 7,067 21,628 20,848 Industrial 1,140 1,061 3,270 3,177 Total depreciation and amortization $ 24,329 $ 23,088 $ 71,865 $ 69,056 Operating income Electronics $ 45,860 $ 34,567 $ 110,783 $ 127,233 Automotive 15,383 11,437 20,642 34,987 Industrial 4,898 6,822 8,409 16,158 Other (a) (1,583) (5,659) (42,476) (17,904) Total operating income 64,558 47,167 97,358 160,474 Interest expense 4,988 5,559 16,261 16,834 Foreign exchange (gain) loss (6,174) 4,968 (9,600) 5,636 Other income, net (1,682) (4,764) (1,643) (3,406) Income before income taxes $ 67,426 $ 41,404 $ 92,340 $ 141,410 (a) Included in “Other” Operating income for the third quarter of 2020 is $0.3 million ($1.6 million year-to-date) of acquisition-related and integration charges related to the IXYS acquisition and other contemplated acquisitions. In addition, there was $1.3 million ($40.9 million year-to-date) of restructuring, impairment and other charges, primarily related to employee termination costs of $1.2 million ($4.6 million year-to-date), and other restructuring charges of $0.1 million ($0.2 million year-to-date), the goodwill impairment charge of $33.8 million recorded in the second quarter associated with the automotive sensors reporting unit within the Automotive segment, and impairment charges of $2.2 million recorded in the first quarter associated with the announced consolidation of a manufacturing facility within the Industrial segment. See Note 4, Goodwill and Other Intangible Assets and Note 6, Restructuring, Impairment and Other Charges, for further discussion. Included in "Other" Operating income for the third quarter of 2019 is $3.2 million ($6.9 million year-to-date) of acquisition integration charges primarily related to the IXYS acquisition. In addition, there were $2.5 million ($11.0 million year-to-date) of restructuring charges primarily related to employee termination costs. The Company’s net sales by country were as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Net sales United States $ 106,121 $ 105,292 $ 285,901 $ 340,811 China 126,506 101,960 314,547 316,553 Other countries (a) 158,939 154,719 444,551 507,986 Total net sales $ 391,566 $ 361,971 $ 1,044,999 $ 1,165,350 The Company’s long-lived assets by country were as follows: (in thousands) September 26, December 28, Long-lived assets United States $ 52,009 $ 58,081 China 82,956 88,306 Mexico 68,346 73,096 Germany 37,611 36,025 Philippines 64,171 51,738 Other countries (a) 34,777 37,371 Total long-lived assets $ 339,870 $ 344,617 The Company’s additions to long-lived assets by country were as follows: Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 Additions to long-lived assets United States $ 2,712 $ 4,972 China 6,414 12,418 Mexico 7,291 12,650 Germany 3,793 4,335 Philippines 15,331 9,546 Other countries (a) 1,152 3,454 Total additions to long-lived assets $ 36,693 $ 47,375 (a) Each country included in other countries is less than 10% of net sales.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Other Information (Policies)	9 Months Ended
	Sep. 26, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company’s accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with U.S. Generally Accepted Accounting Principles (“GAAP”) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the consolidated balance sheets, statements of net income and comprehensive income, statements of cash flows, and statement of stockholders' equity prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. They have been prepared in accordance with accounting policies described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 28, 2019 which should be read in conjunction with the disclosures therein. In the opinion of management, all adjustments considered necessary for a fair presentation have been included and are of a normal, recurring nature. Operating results for interim periods are not necessarily indicative of annual operating results.
Revenue Recognition	Revenue Recognition Revenue Disaggregation The following tables disaggregate the Company’s revenue by primary business units for the three and nine months ended September 26, 2020 and September 28, 2019: Three Months Ended September 26, 2020 Nine Months Ended September 26, 2020 (in thousands) Electronics Automotive Industrial Electronics Automotive Industrial Electronics – Passive Products and Sensors $ 108,253 $ — $ — $ 108,253 $ 285,697 $ — $ — $ 285,697 Electronics – Semiconductor 147,096 — — 147,096 407,112 — — 407,112 Passenger Car Products — 52,691 — 52,691 — 135,645 — 135,645 Automotive Sensors — 26,093 — 26,093 — 64,166 — 64,166 Commercial Vehicle Products — 25,940 — 25,940 — 71,682 — 71,682 Industrial Products — — 31,493 31,493 — — 80,697 80,697 Total $ 255,349 $ 104,724 $ 31,493 $ 391,566 $ 692,809 $ 271,493 $ 80,697 $ 1,044,999 Three Months Ended September 28, 2019 Nine Months Ended September 28, 2019 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Electronics – Passive Products and Sensors $ 94,766 $ — $ — $ 94,766 $ 311,624 $ — $ — $ 311,624 Electronics – Semiconductor 132,486 — — 132,486 440,575 — — 440,575 Passenger Car Products — 53,889 — 53,889 — 164,348 — 164,348 Automotive Sensors — 23,877 — 23,877 — 74,616 — 74,616 Commercial Vehicle Products — 26,915 — 26,915 — 87,850 — 87,850 Industrial Products — — 30,038 30,038 — — 86,337 86,337 Total $ 227,252 $ 104,681 $ 30,038 $ 361,971 $ 752,199 $ 326,814 $ 86,337 $ 1,165,350 See Note 14, Segment Information for net sales by segment and countries. Revenue Recognition The Company recognizes revenue on product sales in the period in which the Company satisfies its performance obligation and control of the product is transferred to the customer. The Company’s sales arrangements with customers are predominately short term in nature and generally provide for transfer of control at the time of shipment as this is the point at which title and risk of loss of the product transfers to the customer. At the end of each period, for those shipments where title to the products and the risk of loss and rewards of ownership do not transfer until the product has been received by the customer, the Company adjusts revenues and cost of sales for the delay between the time that the products are shipped and when they are received by the customer. The amount of revenue recorded reflects the consideration to which the Company expects to be entitled in exchange for goods and may include adjustments for customer allowance, rebates and price adjustments. The Company’s distribution channels are primarily through direct sales and independent third-party distributors. The Company elected the practical expedient under Accounting Standards Codification ("ASC") 340-40-25-4 to expense commissions when incurred as the amortization period of the commission asset the Company would have otherwise recognized is less than one year. Revenue and Billing The Company generally accepts orders from customers through receipt of purchase orders or electronic data interchange based on written sales agreements and purchasing contracts. Contract pricing and selling agreement terms are based on market factors, costs, and competition. Pricing is often negotiated as an adjustment (premium or discount) from the Company’s published price lists. The customer is invoiced when the Company’s products are shipped to them in accordance with the terms of the sales agreement. As the Company’s standard payment terms are less than one year, the Company elected the practical expedient under ASC 606-10-32-18 to not assess whether a contract has a significant financing component. The Company also elected the practical expedient provided in ASC 606-10-25-18B to treat all product shipping and handling activities as fulfillment activities, and therefore recognize the gross revenue associated with the contract, inclusive of any shipping and handling revenue. Ship and Debit Program Some of the terms of the Company’s sales agreements and normal business conditions provide customers (distributors) the ability to receive price adjustments on products previously shipped and invoiced. This practice is common in the industry and is referred to as a “ship and debit” program. This program allows the distributor to debit the Company for the difference between the distributors’ contracted price and a lower price for specific transactions. Under certain circumstances (usually in a competitive situation or large volume opportunity), a distributor will request authorization for pricing allowances to reduce its price. When the Company approves such a reduction, the distributor is authorized to “debit” its account for the difference between the contracted price and the lower approved price. The Company establishes reserves for this program based on historic activity, electronic distributor inventory levels and actual authorizations for the debit and recognizes these debits as a reduction of revenue. Return to Stock The Company has a return to stock policy whereby certain customers, with prior authorization from Littelfuse management, can return previously purchased goods for full or partial credit. The Company establishes an estimated allowance for these returns based on historic activity. Sales revenue and cost of sales are reduced to anticipate estimated returns. Volume Rebates The Company offers volume based sales incentives to certain customers to encourage greater product sales. If customers achieve their specific quarterly or annual sales targets, they are entitled to rebates. The Company estimates the projected amount of rebates that will be achieved by the customer and recognizes this estimated cost as a reduction to revenue as products are sold.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards In June 2016, the FASB issued ASU No. 2016-13, "Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments." The standard modifies the measurement approach for credit losses on financial instruments, including trade receivables, from an incurred loss method to a current expected credit loss method ("CECL"). The standard requires the measurement of expected credit losses to be based on relevant information, including historical experiences, current conditions and a forecast that is supportable. The Company adopted the new standard on December 29, 2019. The adoption of the standard did not have a material effect on our Condensed Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-13 "Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirement for Fair Value Measurement." ASU 2018-13 modifies the disclosure requirements in Topic 820: "Fair Value Measurement," based on the FASB Concepts Statement, "Conceptual Framework for Financial Reporting - Chapter 8: Notes to Financial Statements," including consideration of costs and benefits. The new standard removes certain disclosures, modifies other disclosures and adds additional disclosures related to fair value measurement. The Company adopted the new standard on December 29, 2019. The adoption of ASU 2018-13 did not have a material impact on our Condensed Consolidated Financial Statements. In August 2018, the FASB issued ASU No. 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic: 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)." ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The Company adopted the new standard on December 29, 2019. The adoption of ASU 2018-15 did not have a material impact on our Condensed Consolidated Financial Statements. In March 2020, the FASB issued ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” This ASU provides optional expedient and exceptions for applying generally accepted accounting principles to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The objective of this is to provide optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting due to the cessation of the London Interbank Offered Rate (LIBOR). The amendments in this update are effective for all entities as of March 12, 2020 through December 31, 2022. The Company does not expect a material effect from the adoption of this guidance on its Condensed Consolidated Financial Statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies and Other Information (Tables)	9 Months Ended
	Sep. 26, 2020
Accounting Policies [Abstract]
Schedule of revenue disaggregation	The following tables disaggregate the Company’s revenue by primary business units for the three and nine months ended September 26, 2020 and September 28, 2019: Three Months Ended September 26, 2020 Nine Months Ended September 26, 2020 (in thousands) Electronics Automotive Industrial Electronics Automotive Industrial Electronics – Passive Products and Sensors $ 108,253 $ — $ — $ 108,253 $ 285,697 $ — $ — $ 285,697 Electronics – Semiconductor 147,096 — — 147,096 407,112 — — 407,112 Passenger Car Products — 52,691 — 52,691 — 135,645 — 135,645 Automotive Sensors — 26,093 — 26,093 — 64,166 — 64,166 Commercial Vehicle Products — 25,940 — 25,940 — 71,682 — 71,682 Industrial Products — — 31,493 31,493 — — 80,697 80,697 Total $ 255,349 $ 104,724 $ 31,493 $ 391,566 $ 692,809 $ 271,493 $ 80,697 $ 1,044,999 Three Months Ended September 28, 2019 Nine Months Ended September 28, 2019 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Electronics – Passive Products and Sensors $ 94,766 $ — $ — $ 94,766 $ 311,624 $ — $ — $ 311,624 Electronics – Semiconductor 132,486 — — 132,486 440,575 — — 440,575 Passenger Car Products — 53,889 — 53,889 — 164,348 — 164,348 Automotive Sensors — 23,877 — 23,877 — 74,616 — 74,616 Commercial Vehicle Products — 26,915 — 26,915 — 87,850 — 87,850 Industrial Products — — 30,038 30,038 — — 86,337 86,337 Total $ 227,252 $ 104,681 $ 30,038 $ 361,971 $ 752,199 $ 326,814 $ 86,337 $ 1,165,350

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 26, 2020
Inventory Disclosure [Abstract]
Schedule of inventory	The components of inventories at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Raw materials $ 81,849 $ 76,732 Work in process 90,494 84,561 Finished goods 105,425 110,388 Inventory Reserves (33,936) (34,174) Total $ 243,832 $ 237,507

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	9 Months Ended
	Sep. 26, 2020
Property, Plant and Equipment [Abstract]
Schedule of components of net property, plant, and equipment	The components of net property, plant, and equipment at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Land $ 23,438 $ 24,758 Building 122,914 108,501 Equipment 656,681 631,273 Accumulated depreciation and amortization (463,163) (419,915) Total $ 339,870 $ 344,617

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 26, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill	The amounts for goodwill and changes in the carrying value by segment for the nine months ended September 26, 2020 are as follows: (in thousands) Electronics Automotive Industrial Total As of December 28, 2019 $ 650,796 $ 131,321 $ 38,472 $ 820,589 Impairments — (33,841) — (33,841) Currency translation 11,122 1,988 (67) 13,043 As of September 26, 2020 $ 661,918 $ 99,468 $ 38,405 $ 799,791
Schedule of finite-lived intangible assets	The components of other intangible assets as of September 26, 2020 and December 28, 2019 are as follows: As of September 26, 2020 (in thousands) Gross Accumulated Amortization Net Book Value Land use rights $ 9,913 $ 1,895 $ 8,018 Patents, licenses and software 133,737 $ 88,142 $ 45,595 Distribution network 43,547 38,107 5,440 Customer relationships, trademarks, and tradenames 365,300 128,194 237,106 Total $ 552,497 $ 256,338 $ 296,159 As of December 28, 2019 (in thousands) Gross Accumulated Amortization Net Book Value Land use rights $ 9,649 $ 1,730 $ 7,919 Patents, licenses and software 131,164 78,828 52,336 Distribution network 43,239 36,163 7,076 Customer relationships, trademarks, and tradenames 360,534 106,618 253,916 Total $ 544,586 $ 223,339 $ 321,247
Schedule of finite-lived intangible assets, future amortization expense	Estimated annual amortization expense related to intangible assets with definite lives as of September 26, 2020 is as follows: (in thousands) Amount 2020 $ 41,742 2021 38,258 2022 37,274 2023 32,492 2024 29,695 2025 and thereafter 146,610 Total $ 326,071

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	9 Months Ended
	Sep. 26, 2020
Payables and Accruals [Abstract]
Schedule of components of accrued liabilities	The components of accrued liabilities as of September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, 2020 December 28, 2019 Employee-related liabilities $ 49,805 $ 40,774 Operating lease liability 6,866 7,259 Interest 2,747 5,058 Professional services 2,869 3,986 Restructuring liability 4,542 2,679 Other non-income taxes 3,509 1,940 Other 28,099 22,424 Total $ 98,437 $ 84,120

Restructuring, Impairment and_2

Restructuring, Impairment and Other Charges (Tables)	9 Months Ended
	Sep. 26, 2020
Restructuring and Related Activities [Abstract]
Schedule of restructuring, impairment and other charges	The Company recorded restructuring, impairment and other charges for the three and nine months ended September 26, 2020 and September 28, 2019 as follows: Three months ended September 26, 2020 Nine months ended September 26, 2020 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Employee terminations $ 388 $ 162 $ 648 $ 1,198 $ 2,125 $ 770 $ 1,719 $ 4,614 Other restructuring charges — — 79 79 — 108 104 212 Total restructuring charges 388 162 727 1,277 2,125 878 1,823 4,826 Impairment — — — — — 33,841 2,237 36,078 Total $ 388 $ 162 $ 727 $ 1,277 $ 2,125 $ 34,719 $ 4,060 $ 40,904 Three months ended September 28, 2019 Nine months ended September 28, 2019 (in thousands) Electronics Automotive Industrial Total Electronics Automotive Industrial Total Employee terminations $ 655 $ 109 $ 49 $ 813 $ 4,153 $ 3,955 $ 770 $ 8,878 Other restructuring charges 128 1,150 124 1,402 141 1,240 374 1,755 Total restructuring charges 783 1,259 173 2,215 4,294 5,195 1,144 10,633 Impairment — 322 — 322 — 322 — 322 Total $ 783 $ 1,581 $ 173 $ 2,537 $ 4,294 $ 5,517 $ 1,144 $ 10,955

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 26, 2020
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	The carrying amounts of debt at September 26, 2020 and December 28, 2019 are as follows: (in thousands) September 26, December 28, Revolving Credit Facility $ 180,000 $ — Term Loan — 145,000 Euro Senior Notes, Series A due 2023 136,417 129,808 Euro Senior Notes, Series B due 2028 110,766 105,400 U.S. Senior Notes, Series A due 2022 25,000 25,000 U.S. Senior Notes, Series B due 2027 100,000 100,000 U.S. Senior Notes, Series A due 2025 50,000 50,000 U.S. Senior Notes, Series B due 2030 125,000 125,000 Other 2,619 2,619 Unamortized debt issuance costs (4,295) (3,669) Total debt 725,507 679,158 Less: Current maturities — (10,000) Total long-term debt $ 725,507 $ 669,158

Fair Value of Assets and Liab_2

Fair Value of Assets and Liabilities (Tables)	9 Months Ended
	Sep. 26, 2020
Fair Value Disclosures [Abstract]
Schedule of fair value, assets measured on recurring basis	The following table presents assets measured at fair value by classification within the fair value hierarchy as of September 26, 2020: Fair Value Measurements Using (in thousands) Quoted Prices in Significant Significant Total Cash Equivalents $ 92,472 $ — $ — $ 92,472 Investments in equity securities 15,042 — — 15,042 Mutual funds 11,692 — — 11,692 The following table presents assets measured at fair value by classification within the fair value hierarchy as of December 28, 2019: Fair Value Measurements Using (in thousands) Quoted Prices in Significant Significant Total Cash Equivalents $ 118,999 $ — $ — $ 118,999 Investments in equity securities 12,969 — — 12,969 Mutual funds 10,464 — — 10,464
Schedule of fair value, by balance sheet grouping	The carrying value and estimated fair values of the Company’s Euro Senior Notes, Series A and Series B and USD Senior Notes, Series A and Series B, as of September 26, 2020 and December 28, 2019 were as follows: September 26, 2020 December 28, 2019 (in thousands) Carrying Estimated Carrying Estimated Euro Senior Notes, Series A due 2023 $ 136,417 $ 136,686 $ 129,808 $ 131,710 Euro Senior Notes, Series B due 2028 110,766 114,947 105,400 110,336 USD Senior Notes, Series A due 2022 25,000 25,460 25,000 25,054 USD Senior Notes, Series B due 2027 100,000 109,367 100,000 102,548 USD Senior Notes, Series A due 2025 50,000 53,323 50,000 50,775 USD Senior Notes, Series B due 2030 125,000 138,340 125,000 127,701
Details of impairment of long-lived assets held and used by asset	The second quarter of 2020 goodwill impairment charge was the result of measuring a reporting unit at fair value on a nonrecurring basis as shown below: Nine Months Ended September 26, 2020 September 26, 2020 (in thousands) Impairment Charge Estimated Fair Value Measurement (Level 3) Carrying Value Goodwill $33,841 $8,953 $ 9,449

Benefit Plans (Tables)

Benefit Plans (Tables)	9 Months Ended
	Sep. 26, 2020
Retirement Benefits [Abstract]
Schedule of net benefit costs	The components of net periodic benefit cost for the three and nine months ended September 26, 2020 and September 28, 2019 were as follows: For the Three Months Ended For the Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Components of net periodic benefit cost: Service cost $ 615 $ 509 $ 1,825 $ 1,523 Interest cost 511 777 1,655 2,374 Expected return on plan assets (422) (773) (1,551) (2,384) Amortization of prior service and net actuarial loss 279 60 688 184 Net periodic benefit cost $ 983 $ 573 $ 2,617 $ 1,697

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 26, 2020
Equity [Abstract]
Schedule of components of comprehensive income (loss)	Changes in other comprehensive income (loss) by component were as follows: (in thousands) Three Months Ended Three Months Ended Pre-tax Tax Net of Tax Pre-tax Tax Net of Tax Defined benefit pension plan and other adjustments $ 273 $ (290) $ 563 $ 155 $ 18 $ 137 Foreign currency translation adjustments 16,418 — 16,418 (17,163) — (17,163) Total change in other comprehensive income (loss) $ 16,691 $ (290) $ 16,981 $ (17,008) $ 18 $ (17,026) (in thousands) Nine Months Ended September 26, 2020 Nine Months Ended September 28, 2019 Pre-tax Tax Net of Tax Pre-tax Tax Net of Tax Defined benefit pension plan and other adjustments $ (12,270) $ (2,555) $ (9,715) $ 278 $ 29 $ 249 Foreign currency translation adjustments 9,300 — 9,300 (14,933) — (14,933) Total change in other comprehensive loss $ (2,970) $ (2,555) $ (415) $ (14,655) $ 29 $ (14,684)
Schedule of accumulated other comprehensive income (loss)	The following tables set forth the changes in accumulated other comprehensive income (loss) by component for the nine months ended September 26, 2020 and September 28, 2019: (in thousands) Pension and Foreign Accumulated Balance at December 28, 2019 $ (18,046) $ (88,777) $ (106,823) Activity in the period (9,715) 9,300 (415) Balance at September 26, 2020 $ (27,761) $ (79,477) $ (107,238) (in thousands) Pension and Foreign Accumulated Balance at December 29, 2018 $ (9,959) $ (87,965) $ (97,924) Activity in the period 249 (14,933) (14,684) Balance at September 28, 2019 $ (9,710) $ (102,898) $ (112,608)
Summary of reclassification out of accumulated other comprehensive income	Amounts reclassified from accumulated other comprehensive income (loss) to earnings for the three and nine months ended September 26, 2020 and September 28, 2019 were as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Pension and Postemployment plans: Amortization of prior service and net actuarial loss $ 452 $ 60 $ 1,226 $ 184

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 26, 2020
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	The following table sets forth the computation of basic and diluted earnings per share: Three Months Ended Nine Months Ended (in thousands, except per share amounts) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Numerator: Net income as reported $ 55,356 $ 35,647 $ 71,009 $ 116,428 Denominator: Weighted average shares outstanding Basic 24,357 24,482 24,354 24,646 Effect of dilutive securities 216 202 181 248 Diluted 24,573 24,684 24,535 24,894 Earnings Per Share: Basic earnings per share $ 2.27 $ 1.46 $ 2.92 $ 4.72 Diluted earnings per share $ 2.25 $ 1.44 $ 2.89 $ 4.68

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 26, 2020
Related Party Transactions [Abstract]
Schedule of related party transactions	For the Three Months Ended September 26, 2020 For the Three Months Ended September 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Sales to related party $ 0.4 $ — $ — $ 0.2 $ — $ — Purchase material/service from related party 0.8 — 2.4 0.8 0.1 1.7 For the Nine Months Ended September 26, 2020 For the Nine Months Ended September 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Sales to related party $ 1.1 $ — $ — $ 0.4 $ — $ — Purchase material/service from related party 1.8 — 5.8 2.4 0.3 5.5 September 26, 2020 December 28, 2019 (in millions) Powersem EB Tech ATEC Powersem EB Tech ATEC Accounts Receivable balance $ 0.1 $ — $ — $ — $ — $ — Accounts Payable balance 0.1 — 0.1 0.2 — 0.1

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 26, 2020
Segment Reporting [Abstract]
Schedule of segment reporting information, by segment	Segment information is summarized as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Net sales Electronics $ 255,349 $ 227,252 $ 692,809 $ 752,199 Automotive 104,724 104,681 271,493 326,814 Industrial 31,493 30,038 80,697 86,337 Total net sales $ 391,566 $ 361,971 $ 1,044,999 $ 1,165,350 Depreciation and amortization Electronics $ 15,819 $ 14,960 $ 46,967 45,031 Automotive 7,370 7,067 21,628 20,848 Industrial 1,140 1,061 3,270 3,177 Total depreciation and amortization $ 24,329 $ 23,088 $ 71,865 $ 69,056 Operating income Electronics $ 45,860 $ 34,567 $ 110,783 $ 127,233 Automotive 15,383 11,437 20,642 34,987 Industrial 4,898 6,822 8,409 16,158 Other (a) (1,583) (5,659) (42,476) (17,904) Total operating income 64,558 47,167 97,358 160,474 Interest expense 4,988 5,559 16,261 16,834 Foreign exchange (gain) loss (6,174) 4,968 (9,600) 5,636 Other income, net (1,682) (4,764) (1,643) (3,406) Income before income taxes $ 67,426 $ 41,404 $ 92,340 $ 141,410 (a) Included in “Other” Operating income for the third quarter of 2020 is $0.3 million ($1.6 million year-to-date) of acquisition-related and integration charges related to the IXYS acquisition and other contemplated acquisitions. In addition, there was $1.3 million ($40.9 million year-to-date) of restructuring, impairment and other charges, primarily related to employee termination costs of $1.2 million ($4.6 million year-to-date), and other restructuring charges of $0.1 million ($0.2 million year-to-date), the goodwill impairment charge of $33.8 million recorded in the second quarter associated with the automotive sensors reporting unit within the Automotive segment, and impairment charges of $2.2 million recorded in the first quarter associated with the announced consolidation of a manufacturing facility within the Industrial segment. See Note 4, Goodwill and Other Intangible Assets and Note 6, Restructuring, Impairment and Other Charges, for further discussion.
Schedule of disclosure on geographic areas, long-lived assets in individual foreign countries by country	The Company’s net sales by country were as follows: Three Months Ended Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 September 26, 2020 September 28, 2019 Net sales United States $ 106,121 $ 105,292 $ 285,901 $ 340,811 China 126,506 101,960 314,547 316,553 Other countries (a) 158,939 154,719 444,551 507,986 Total net sales $ 391,566 $ 361,971 $ 1,044,999 $ 1,165,350 The Company’s long-lived assets by country were as follows: (in thousands) September 26, December 28, Long-lived assets United States $ 52,009 $ 58,081 China 82,956 88,306 Mexico 68,346 73,096 Germany 37,611 36,025 Philippines 64,171 51,738 Other countries (a) 34,777 37,371 Total long-lived assets $ 339,870 $ 344,617 The Company’s additions to long-lived assets by country were as follows: Nine Months Ended (in thousands) September 26, 2020 September 28, 2019 Additions to long-lived assets United States $ 2,712 $ 4,972 China 6,414 12,418 Mexico 7,291 12,650 Germany 3,793 4,335 Philippines 15,331 9,546 Other countries (a) 1,152 3,454 Total additions to long-lived assets $ 36,693 $ 47,375 (a) Each country included in other countries is less than 10% of net sales.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Other Information (Details Textual) customer in Thousands	9 Months Ended
	Sep. 26, 2020customer
Accounting Policies [Abstract]
Number of customers (over)	100

Summary of Significant Accoun_5

Summary of Significant Accounting Policies and Other Information - Revenue Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Disaggregation of Revenue
Net sales	$ 391,566	$ 361,971	$ 1,044,999	$ 1,165,350
Electronics – Passive Products and Sensors
Disaggregation of Revenue
Net sales	108,253	94,766	285,697	311,624
Electronics – Semiconductor
Disaggregation of Revenue
Net sales	147,096	132,486	407,112	440,575
Passenger Car Products
Disaggregation of Revenue
Net sales	52,691	53,889	135,645	164,348
Automotive Sensors
Disaggregation of Revenue
Net sales	26,093	23,877	64,166	74,616
Commercial Vehicle Products
Disaggregation of Revenue
Net sales	25,940	26,915	71,682	87,850
Industrial Products
Disaggregation of Revenue
Net sales	31,493	30,038	80,697	86,337
Electronics Segment
Disaggregation of Revenue
Net sales	255,349	227,252	692,809	752,199
Electronics Segment | Electronics – Passive Products and Sensors
Disaggregation of Revenue
Net sales	108,253	94,766	285,697	311,624
Electronics Segment | Electronics – Semiconductor
Disaggregation of Revenue
Net sales	147,096	132,486	407,112	440,575
Electronics Segment | Passenger Car Products
Disaggregation of Revenue
Net sales	0	0	0	0
Electronics Segment | Automotive Sensors
Disaggregation of Revenue
Net sales	0	0	0	0
Electronics Segment | Commercial Vehicle Products
Disaggregation of Revenue
Net sales	0	0	0	0
Electronics Segment | Industrial Products
Disaggregation of Revenue
Net sales	0	0	0	0
Automotive Segment
Disaggregation of Revenue
Net sales	104,724	104,681	271,493	326,814
Automotive Segment | Electronics – Passive Products and Sensors
Disaggregation of Revenue
Net sales	0	0	0	0
Automotive Segment | Electronics – Semiconductor
Disaggregation of Revenue
Net sales	0	0	0	0
Automotive Segment | Passenger Car Products
Disaggregation of Revenue
Net sales	52,691	53,889	135,645	164,348
Automotive Segment | Automotive Sensors
Disaggregation of Revenue
Net sales	26,093	23,877	64,166	74,616
Automotive Segment | Commercial Vehicle Products
Disaggregation of Revenue
Net sales	25,940	26,915	71,682	87,850
Automotive Segment | Industrial Products
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment
Disaggregation of Revenue
Net sales	31,493	30,038	80,697	86,337
Industrial Segment | Electronics – Passive Products and Sensors
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment | Electronics – Semiconductor
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment | Passenger Car Products
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment | Automotive Sensors
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment | Commercial Vehicle Products
Disaggregation of Revenue
Net sales	0	0	0	0
Industrial Segment | Industrial Products
Disaggregation of Revenue
Net sales	$ 31,493	$ 30,038	$ 80,697	$ 86,337

Inventories - Components of Inv

Inventories - Components of Inventories (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 81,849	$ 76,732
Work in process	90,494	84,561
Finished goods	105,425	110,388
Inventory Reserves	(33,936)	(34,174)
Total	$ 243,832	$ 237,507

Property, Plant, and Equipmen_2

Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Property, Plant and Equipment
Accumulated depreciation and amortization	$ (463,163)		$ (463,163)		$ (419,915)
Total	339,870		339,870		344,617
Depreciation	14,200	$ 13,300	41,953	$ 38,988
Land
Property, Plant and Equipment
Property, plant, and equipment, gross	23,438		23,438		24,758
Building
Property, Plant and Equipment
Property, plant, and equipment, gross	122,914		122,914		108,501
Equipment
Property, Plant and Equipment
Property, plant, and equipment, gross	$ 656,681		$ 656,681		$ 631,273

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Amounts for Goodwill and Changes in Carrying Value by Operating Segment (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Goodwill
Balance				$ 820,589
Impairments	$ 0	$ (33,800)	$ 0	(33,841)	$ 0
Currency translation				13,043
Balance	799,791			799,791
Electronics
Goodwill
Balance				650,796
Impairments				0
Currency translation				11,122
Balance	661,918			661,918
Automotive
Goodwill
Balance				131,321
Impairments				(33,841)
Currency translation				1,988
Balance	99,468			99,468
Industrial
Goodwill
Balance				38,472
Impairments				0
Currency translation				(67)
Balance	$ 38,405			$ 38,405

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Details of Other Intangible Assets and Related Future Amortization Expense (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Finite-Lived Intangible Assets
Gross Carrying Value	$ 552,497	$ 544,586
Accumulated Amortization	256,338	223,339
Net Book Value	296,159	321,247
Land use rights
Finite-Lived Intangible Assets
Gross Carrying Value	9,913	9,649
Accumulated Amortization	1,895	1,730
Net Book Value	8,018	7,919
Patents, licenses and software
Finite-Lived Intangible Assets
Gross Carrying Value	133,737	131,164
Accumulated Amortization	88,142	78,828
Net Book Value	45,595	52,336
Distribution network
Finite-Lived Intangible Assets
Gross Carrying Value	43,547	43,239
Accumulated Amortization	38,107	36,163
Net Book Value	5,440	7,076
Customer relationships, trademarks, and tradenames
Finite-Lived Intangible Assets
Gross Carrying Value	365,300	360,534
Accumulated Amortization	128,194	106,618
Net Book Value	$ 237,106	$ 253,916

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Estimated Amortization Expense Related to Intangible Assets with Definite Lives (Details) $ in Thousands	Sep. 26, 2020USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2020	$ 41,742
2021	38,258
2022	37,274
2023	32,492
2024	29,695
2025 and thereafter	146,610
Total	$ 326,071

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Goodwill [Line Items]
Goodwill impairment charge	$ 0	$ 33,800		$ 0	$ 33,841	$ 0
Goodwill	799,791				799,791		$ 820,589
Amortization of intangibles	10,104			$ 9,827	29,912	$ 30,068
Impairment of intangibles			$ 300
Automotive Sensors
Goodwill [Line Items]
Goodwill	$ 9,400				$ 9,400

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Payables and Accruals [Abstract]
Employee-related liabilities	$ 49,805	$ 40,774
Operating lease liability	6,866	7,259
Interest	2,747	5,058
Professional services	2,869	3,986
Restructuring liability	4,542	2,679
Other non-income taxes	3,509	1,940
Other	28,099	22,424
Total	$ 98,437	$ 84,120

Restructuring, Impairment and_3

Restructuring, Impairment and Other Charges (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Restructuring Cost and Reserve
Total restructuring charges	$ 1,277		$ 2,215	$ 4,826	$ 10,633
Impairment charges	0		322	36,078	322
Restructuring costs	1,277		2,537	40,904	10,955
Restructuring reserves	4,500			4,500		$ 2,700
Employee terminations
Restructuring Cost and Reserve
Total restructuring charges	1,198		813	4,614	8,878
Other restructuring charges
Restructuring Cost and Reserve
Total restructuring charges	79		1,402	212	1,755
Electronics
Restructuring Cost and Reserve
Total restructuring charges	388		783	2,125	4,294
Impairment charges	0		0	0	0
Restructuring costs	388		783	2,125	4,294
Electronics | Employee terminations
Restructuring Cost and Reserve
Total restructuring charges	388		655	2,125	4,153
Electronics | Other restructuring charges
Restructuring Cost and Reserve
Total restructuring charges	0		128	0	141
Automotive
Restructuring Cost and Reserve
Total restructuring charges	162		1,259	878	5,195
Impairment charges	0		322	33,841	322
Restructuring costs	162		1,581	34,719	5,517
Automotive | Employee terminations
Restructuring Cost and Reserve
Total restructuring charges	162		109	770	3,955
Automotive | Other restructuring charges
Restructuring Cost and Reserve
Total restructuring charges	0		1,150	108	1,240
Industrial
Restructuring Cost and Reserve
Total restructuring charges	727		173	1,823	1,144
Impairment charges	0		0	2,237	0
Restructuring costs	727		173	4,060	1,144
Industrial | Employee terminations
Restructuring Cost and Reserve
Total restructuring charges	648		49	1,719	770
Industrial | Other restructuring charges
Restructuring Cost and Reserve
Total restructuring charges	$ 79		$ 124	$ 104	$ 374
Industrial | Facility Closing
Restructuring Cost and Reserve
Impairment charges		$ 2,200

Debt - Carrying Amounts of Long

Debt - Carrying Amounts of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Apr. 02, 2020	Dec. 28, 2019
Debt Instrument
Unamortized debt issuance costs	$ (4,295)		$ (3,669)
Total debt	725,507		679,158
Less: Current maturities	0		(10,000)
Total long-term debt	725,507		669,158
Revolving Credit Facility
Debt Instrument
Long-term debt, gross	180,000		0
Term Loan
Debt Instrument
Long-term debt, gross	0	$ 140,000	145,000
Senior Notes | Euro Senior Notes, Series A due 2023
Debt Instrument
Long-term debt, gross	136,417		129,808
Senior Notes | Euro Senior Notes, Series B due 2028
Debt Instrument
Long-term debt, gross	110,766		105,400
Senior Notes | U.S. Senior Notes, Series A due 2022
Debt Instrument
Long-term debt, gross	25,000		25,000
Senior Notes | U.S. Senior Notes, Series B due 2027
Debt Instrument
Long-term debt, gross	100,000		100,000
Senior Notes | U.S. Senior Notes, Series A due 2025
Debt Instrument
Long-term debt, gross	50,000		50,000
Senior Notes | U.S. Senior Notes, Series B due 2030
Debt Instrument
Long-term debt, gross	125,000		125,000
Other
Debt Instrument
Long-term debt, gross	$ 2,619		$ 2,619

Debt - Narrative (Details)

Debt - Narrative (Details)	Apr. 03, 2020USD ($)	Mar. 25, 2020USD ($)	Jan. 16, 2018USD ($)	Oct. 13, 2017USD ($)advance	Mar. 04, 2016USD ($)	Sep. 26, 2020USD ($)	Sep. 28, 2019USD ($)	Sep. 26, 2020USD ($)	Sep. 28, 2019USD ($)	Apr. 02, 2020USD ($)	Dec. 28, 2019USD ($)	Nov. 15, 2017USD ($)series	Oct. 12, 2017USD ($)	Feb. 15, 2017USD ($)	Dec. 08, 2016USD ($)series	Dec. 08, 2016EUR (€)series
Debt Instrument
Proceeds of revolving credit facility		$ 100,000,000						$ 240,000,000	$ 0
Cash paid during the period for interest						$ 6,400,000	$ 6,400,000	$ 17,228,000	$ 17,872,000
Credit Agreement
Debt Instrument
Debt term (in years)					5 years
Maximum borrowing capacity					$ 700,000,000
Additional uncommitted borrowing capacity				$ 300,000,000	150,000,000
Additional uncommitted borrowing capacity, minimum increments					$ 25,000,000
Number of advances | advance				2
Effective interest rate (percent)						1.90%		1.90%
Letter of credit outstanding (less than)						$ 0		$ 0
Credit Agreement | Minimum
Debt Instrument
Commitment fee (percent)					0.125%
Credit Agreement | Maximum
Debt Instrument
Commitment fee (percent)					0.20%
Credit Agreement | LIBOR | Minimum
Debt Instrument
Basis spread on variable rate (percent)					1.25%
Credit Agreement | LIBOR | Maximum
Debt Instrument
Basis spread on variable rate (percent)					2.00%
Credit Agreement | Base Rate | Minimum
Debt Instrument
Basis spread on variable rate (percent)					0.25%
Credit Agreement | Base Rate | Maximum
Debt Instrument
Basis spread on variable rate (percent)					1.00%
Credit Agreement | Revolving Credit Facility
Debt Instrument
Maximum borrowing capacity				$ 700,000,000	$ 575,000,000								$ 575,000,000
Remaining borrowing capacity						245,100,000		245,100,000
Credit Agreement | Term Loan Credit Facility
Debt Instrument
Maximum borrowing capacity, credit facility				200,000,000	$ 125,000,000
Proceeds from issuance of debt			$ 75,000,000	$ 125,000,000
Quarterly payments, percentage of loan (percent)				1.25%
Periodic payment				$ 2,500,000
Repayments of debt								5,000,000
Term Loan
Debt Instrument
Elimination of unsecured team loan facility	$ 200,000,000
Long-term debt, gross						0		0		$ 140,000,000	$ 145,000,000
Senior Notes | Euro Senior Notes, Series A and B
Debt Instrument
Face amount of debt | €																€ 212,000,000
Number of series | series															2	2
Senior Notes | Euro Senior Notes, Series A due 2023
Debt Instrument
Long-term debt, gross						136,417,000		136,417,000			129,808,000
Face amount of debt | €																€ 117,000,000
Stated interest rate (percent)															1.14%	1.14%
Senior Notes | Euro Senior Notes, Series B due 2028
Debt Instrument
Long-term debt, gross						110,766,000		110,766,000			105,400,000
Face amount of debt | €																€ 95,000,000
Stated interest rate (percent)															1.83%	1.83%
Senior Notes | U.S. Senior Notes, Series A and B
Debt Instrument
Face amount of debt															$ 125,000,000
Number of series | series															2	2
Senior Notes | U.S. Senior Notes, Series A
Debt Instrument
Face amount of debt														$ 25,000,000
Stated interest rate (percent)														3.03%
Senior Notes | U.S. Senior Notes, Series B
Debt Instrument
Face amount of debt														$ 100,000,000
Stated interest rate (percent)														3.74%
Senior Notes | US Senior Notes A and B Due 2025 and 2030
Debt Instrument
Face amount of debt												$ 175,000,000
Number of series | series												2
Senior Notes | U.S. Senior Notes, Series A due 2025
Debt Instrument
Long-term debt, gross						50,000,000		50,000,000			50,000,000
Face amount of debt			$ 50,000,000
Stated interest rate (percent)			3.48%
Senior Notes | U.S. Senior Notes, Series B due 2030
Debt Instrument
Long-term debt, gross						$ 125,000,000		$ 125,000,000			$ 125,000,000
Face amount of debt			$ 125,000,000
Stated interest rate (percent)			3.78%

Fair Value of Assets and Liab_3

Fair Value of Assets and Liabilities - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash Equivalents	$ 92,472	$ 118,999
Investments in equity securities	15,042	12,969
Mutual funds	11,692	10,464
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash Equivalents	92,472	118,999
Investments in equity securities	15,042	12,969
Mutual funds	11,692	10,464
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash Equivalents	0	0
Investments in equity securities	0	0
Mutual funds	0	0
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash Equivalents	0	0
Investments in equity securities	0	0
Mutual funds	$ 0	$ 0

Fair Value of Assets and Liab_4

Fair Value of Assets and Liabilities - Carrying Value and Estimated Fair Value of Senior Notes (Details) - Senior Notes - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Carrying Value | Euro Senior Notes, Series A due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	$ 136,417	$ 129,808
Carrying Value | Euro Senior Notes, Series B due 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	110,766	105,400
Carrying Value | U.S. Senior Notes, Series A due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	25,000	25,000
Carrying Value | U.S. Senior Notes, Series B due 2027
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	100,000	100,000
Carrying Value | U.S. Senior Notes, Series A due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	50,000	50,000
Carrying Value | U.S. Senior Notes, Series B due 2030
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	125,000	125,000
Estimated Fair Value | Euro Senior Notes, Series A due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	136,686	131,710
Estimated Fair Value | Euro Senior Notes, Series B due 2028
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	114,947	110,336
Estimated Fair Value | U.S. Senior Notes, Series A due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	25,460	25,054
Estimated Fair Value | U.S. Senior Notes, Series B due 2027
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	109,367	102,548
Estimated Fair Value | U.S. Senior Notes, Series A due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	53,323	50,775
Estimated Fair Value | U.S. Senior Notes, Series B due 2030
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Long-term debt fair value	$ 138,340	$ 127,701

Fair Value of Assets and Liab_5

Fair Value of Assets and Liabilities - Narrative (Details) - USD ($) $ in Thousands	Mar. 23, 2020	Sep. 26, 2020	Mar. 28, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges		$ 0		$ 322	$ 36,078	$ 322
Investments in equity securities		15,042			15,042		$ 12,969
Notional amount of derivatives							16,000
Gain on derivatives	$ 200
Patents
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges			$ 300
Land and Building
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges			$ 1,900
Other Expense (Income)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges		100				$ 2,800
Investments in equity securities		$ 500			$ 500		$ 400

Fair Value of Assets and Liab_6

Fair Value of Assets and Liabilities - Impairment of Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Dec. 28, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Goodwill	$ 799,791	$ 820,589
Fair Value, Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment Charge	33,841
Fair Value, Nonrecurring | Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Goodwill	8,953
Fair Value, Nonrecurring | Significant Unobservable Inputs (Level 3) | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Goodwill	$ 9,449

Benefit Plans - Benefit Plan Ex

Benefit Plans - Benefit Plan Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Retirement Benefits [Abstract]
Service cost	$ 615	$ 509	$ 1,825	$ 1,523
Interest cost	511	777	1,655	2,374
Expected return on plan assets	(422)	(773)	(1,551)	(2,384)
Amortization of prior service and net actuarial loss	279	60	688	184
Net periodic benefit cost	$ 983	$ 573	$ 2,617	$ 1,697

Benefit Plans - Narrative (Deta

Benefit Plans - Narrative (Details) $ in Thousands, £ in Millions	Apr. 06, 2020USD ($)	Apr. 06, 2020GBP (£)	Sep. 26, 2020USD ($)	Jun. 27, 2020USD ($)	Jun. 27, 2020GBP (£)	Sep. 28, 2019USD ($)	Dec. 31, 2021USD ($)	Sep. 26, 2020USD ($)	Sep. 28, 2019USD ($)	Apr. 07, 2020USD ($)
Defined Benefit Plan Disclosure
Contributions expected			$ 2,300					$ 2,300
Defined benefit plan expense			983			$ 573		2,617	$ 1,697
Estimated decrease in pension cost										$ 36,000
Estimated percent reduction in pension costs										30.00%
Benefit obligation, unamortized actuarial loss	$ 13,400
Cash contribution				$ 10,400	£ 8.4
Pension and postretirement liability and reclassification adjustments
Defined Benefit Plan Disclosure
Benefit obligation, unamortized actuarial loss | £		£ 10.9
Forecast | Minimum
Defined Benefit Plan Disclosure
Estimated settlement charge							$ 18,000
Forecast | Maximum
Defined Benefit Plan Disclosure
Estimated settlement charge							$ 22,000
Foreign Plan
Defined Benefit Plan Disclosure
Defined benefit plan expense			500			$ 200		1,500	$ 600
Other comprehensive income as component of net period benefit cost, before tax			$ 200					$ 500

Other Comprehensive Income - Sc

Other Comprehensive Income - Schedule of Components of Comprehensive Income (Loss) (Details) $ in Thousands, £ in Millions	Apr. 06, 2020USD ($)	Apr. 06, 2020GBP (£)	Sep. 26, 2020USD ($)	Jun. 27, 2020USD ($)	Mar. 28, 2020USD ($)	Sep. 28, 2019USD ($)	Jun. 29, 2019USD ($)	Mar. 30, 2019USD ($)	Sep. 26, 2020USD ($)	Sep. 28, 2019USD ($)
Other Comprehensive Income (Loss)
Pre-tax			$ 16,691			$ (17,008)			$ (2,970)	$ (14,655)
Tax			(290)			18			(2,555)	29
Total change in other comprehensive income (loss)			16,981	$ (2,417)	$ (14,979)	(17,026)	$ (5,731)	$ 8,073	(415)	(14,684)
Benefit obligation, unamortized actuarial loss	$ 13,400
Pension and postretirement liability and reclassification adjustments
Other Comprehensive Income (Loss)
Pre-tax			273			155			(12,270)	278
Tax			(290)			18			(2,555)	29
Total change in other comprehensive income (loss)			563			137			(9,715)	249
Benefit obligation, unamortized actuarial loss | £		£ 10.9
Foreign currency translation adjustment
Other Comprehensive Income (Loss)
Pre-tax			16,418			(17,163)			9,300	(14,933)
Tax			0			0			0	0
Total change in other comprehensive income (loss)			$ 16,418			$ (17,163)			$ 9,300	$ (14,933)

Other Comprehensive Income - _2

Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Sep. 26, 2020	Sep. 28, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	$ 1,462,434	$ 1,476,948	$ 1,496,014	$ 1,509,942	$ 1,505,388	$ 1,478,342	$ 1,496,014	$ 1,478,342
Other comprehensive loss, net of tax	16,981	(2,417)	(14,979)	(17,026)	(5,731)	8,073	(415)	(14,684)
Balance	1,529,562	1,462,434	1,476,948	1,472,212	1,509,942	1,505,388	1,529,562	1,472,212
Accumulated other comprehensive (loss) income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(124,219)	(121,802)	(106,823)	(95,582)	(89,851)	(97,924)	(106,823)	(97,924)
Other comprehensive loss, net of tax	16,981	(2,417)	(14,979)	(17,026)	(5,731)	8,073
Balance	(107,238)	$ (124,219)	(121,802)	(112,608)	$ (95,582)	(89,851)	(107,238)	(112,608)
Pension and postretirement liability and reclassification adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance			(18,046)			(9,959)	(18,046)	(9,959)
Other comprehensive loss, net of tax	563			137			(9,715)	249
Balance	(27,761)			(9,710)			(27,761)	(9,710)
Foreign currency translation adjustment
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance			$ (88,777)			$ (87,965)	(88,777)	(87,965)
Other comprehensive loss, net of tax	16,418			(17,163)			9,300	(14,933)
Balance	$ (79,477)			$ (102,898)			$ (79,477)	$ (102,898)

Other Comprehensive Income - Re

Other Comprehensive Income - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Amortization of prior service and net actuarial loss	$ 253,390	$ 231,025	$ 684,012	$ 737,368
Amortization of prior service and net actuarial loss | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Amortization of prior service and net actuarial loss	$ 452	$ 60	$ 1,226	$ 184

Income Taxes (Details Textual)

Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Income Tax Disclosure [Abstract]
Effective tax rate (percent)	17.90%		13.90%	23.10%	17.70%
Goodwill impairment charge	$ 0	$ 33,800	$ 0	$ 33,841	$ 0

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Sep. 26, 2020	Sep. 28, 2019
Numerator:
Net income as reported	$ 55,356	$ (8,991)	$ 24,644	$ 35,647	$ 43,792	$ 36,989	$ 71,009	$ 116,428
Weighted average shares outstanding
Basic (in shares)	24,357			24,482			24,354	24,646
Effect of dilutive securities (in shares)	216			202			181	248
Diluted (in shares)	24,573			24,684			24,535	24,894
Earnings Per Share:
Basic (loss) earnings per share (in dollars per share)	$ 2.27			$ 1.46			$ 2.92	$ 4.72
Diluted (loss) earnings per share (in dollars per share)	$ 2.25			$ 1.44			$ 2.89	$ 4.68

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended					9 Months Ended
	Sep. 26, 2020	Mar. 28, 2020	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Sep. 26, 2020	Sep. 28, 2019	Apr. 23, 2020	May 01, 2019	Apr. 26, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share
Shares repurchased (in shares)	0		311,786			175,110	579,916
Repurchases of common stock		$ 22,927	$ 49,526	$ 31,955	$ 13,555	$ 22,900	$ 95,000
2018 Share Repurchase Program
Antidilutive Securities Excluded from Computation of Earnings Per Share
Repurchase authorized (in shares)									1,000,000
2019 Share Repurchase Program
Antidilutive Securities Excluded from Computation of Earnings Per Share
Repurchase authorized (in shares)										1,000,000
2020 Share Repurchase Program
Antidilutive Securities Excluded from Computation of Earnings Per Share
Repurchase authorized (in shares)								1,000,000
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded (in shares)	290,262		205,516			194,857	147,090

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	Apr. 26, 2019	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Related Party Transaction
Cost method investments		$ 0.5		$ 0.5
MWT
Related Party Transaction
Loss on disposal	$ 2.6
Powersem
Related Party Transaction
Ownership percentage (percent)		45.00%		45.00%
Revenue from related parties		$ 0.4	$ 0.2	$ 1.1	$ 0.4
Purchase from related party		0.8	0.8	1.8	2.4
Receivable from related parties		0.1		0.1		$ 0
Payables to related parties		$ 0.1		$ 0.1		0.2
EB Tech
Related Party Transaction
Ownership percentage (percent)		19.00%		19.00%
Revenue from related parties		$ 0	0	$ 0	0
Purchase from related party		0	0.1	0	0.3
Receivable from related parties		0		0		0
Payables to related parties		$ 0		$ 0		0
ATEC
Related Party Transaction
Ownership percentage (percent)		24.00%		24.00%
Revenue from related parties		$ 0	0	$ 0	0
Purchase from related party		2.4	$ 1.7	5.8	$ 5.5
Receivable from related parties		0		0		0
Payables to related parties		$ 0.1		$ 0.1		$ 0.1

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Segment Reporting Information
Net sales	$ 391,566	$ 361,971	$ 1,044,999	$ 1,165,350
Depreciation and amortization	24,329	23,088	71,865	69,056
Operating income	64,558	47,167	97,358	160,474
Interest expense	4,988	5,559	16,261	16,834
Foreign exchange (gain) loss	(6,174)	4,968	(9,600)	5,636
Other income, net	(1,682)	(4,764)	(1,643)	(3,406)
Income before income taxes	67,426	41,404	92,340	141,410
Electronics
Segment Reporting Information
Net sales	255,349	227,252	692,809	752,199
Depreciation and amortization	15,819	14,960	46,967	45,031
Automotive
Segment Reporting Information
Net sales	104,724	104,681	271,493	326,814
Depreciation and amortization	7,370	7,067	21,628	20,848
Industrial
Segment Reporting Information
Net sales	31,493	30,038	80,697	86,337
Depreciation and amortization	1,140	1,061	3,270	3,177
Operating Segments | Electronics
Segment Reporting Information
Operating income	45,860	34,567	110,783	127,233
Operating Segments | Automotive
Segment Reporting Information
Operating income	15,383	11,437	20,642	34,987
Operating Segments | Industrial
Segment Reporting Information
Operating income	4,898	6,822	8,409	16,158
Corporate Non-Segment | Other
Segment Reporting Information
Operating income	$ (1,583)	$ (5,659)	$ (42,476)	$ (17,904)

Segment Information - Narrative

Segment Information - Narrative (Details) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 26, 2020USD ($)	Jun. 27, 2020USD ($)	Mar. 28, 2020USD ($)	Sep. 28, 2019USD ($)	Sep. 26, 2020USD ($)segment	Sep. 28, 2019USD ($)
Segment Reporting Information
Number of operating segments | segment					3
Restructuring charges	$ 1,277			$ 2,215	$ 4,826	$ 10,633
Operating Income (Loss)
Segment Reporting Information
Restructuring charges	1,200				4,600
Acquisition related costs				3,200		6,900
Other | Operating Income (Loss)
Segment Reporting Information
Legal, accounting and other expenses	300				1,600
Restructuring charges	1,300				40,900
Automotive
Segment Reporting Information
Restructuring charges	162			1,259	878	5,195
Impairment charges			$ 2,200
Other restructuring charges
Segment Reporting Information
Restructuring charges	79			1,402	212	1,755
Other restructuring charges | Automotive
Segment Reporting Information
Restructuring charges	0			1,150	108	1,240
Facility Closing | Automotive
Segment Reporting Information
Impairment charges		$ 33,800
Employee terminations
Segment Reporting Information
Restructuring charges	1,198			813	4,614	8,878
Employee terminations | IXYS
Segment Reporting Information
Restructuring charges				2,500		11,000
Employee terminations | Automotive
Segment Reporting Information
Restructuring charges	$ 162			$ 109	$ 770	$ 3,955

Segment Information - Revenues

Segment Information - Revenues and Long-lived Assets by Geographical Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Segment Reporting Information
Net sales	$ 391,566	$ 361,971	$ 1,044,999	$ 1,165,350
Long-lived assets	339,870		339,870		$ 344,617
Additions to long-lived assets			36,693	47,375
United States
Segment Reporting Information
Net sales	106,121	105,292	285,901	340,811
Long-lived assets	52,009		52,009		58,081
Additions to long-lived assets			2,712	4,972
China
Segment Reporting Information
Net sales	126,506	101,960	314,547	316,553
Long-lived assets	82,956		82,956		88,306
Additions to long-lived assets			6,414	12,418
Mexico
Segment Reporting Information
Long-lived assets	68,346		68,346		73,096
Additions to long-lived assets			7,291	12,650
Germany
Segment Reporting Information
Long-lived assets	37,611		37,611		36,025
Additions to long-lived assets			3,793	4,335
Philippines
Segment Reporting Information
Long-lived assets	64,171		64,171		51,738
Additions to long-lived assets			15,331	9,546
Other countries
Segment Reporting Information
Net sales	158,939	$ 154,719	444,551	507,986
Long-lived assets	$ 34,777		34,777		$ 37,371
Additions to long-lived assets			$ 1,152	$ 3,454