Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Apr. 04, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 556,642	$ 601,976
Available-for-sale marketable securities, Unrealized Gain	5,072	9,077
Available-for-sale marketable securities, Unrealized (Loss)	(952)	(213)
Available-for-sale marketable securities, Fair Market Value	560,762	610,840
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	65,454	70,418
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	155,337	257,132
Available-for-sale marketable securities, Unrealized Gain	644	1,330
Available-for-sale marketable securities, Unrealized (Loss)	(791)	(158)
Available-for-sale marketable securities, Fair Market Value	155,190	258,304
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	24,492	17,243
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	306,707	254,404
Available-for-sale marketable securities, Unrealized Gain	8	10
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	306,715	254,413
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	13,996	12,173
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	79,190	76,129
Available-for-sale marketable securities, Unrealized Gain	4,340	7,539
Available-for-sale marketable securities, Unrealized (Loss)	(158)	(53)
Available-for-sale marketable securities, Fair Market Value	83,372	83,615
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	25,553	39,896
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	966	979
Available-for-sale marketable securities, Fair Market Value	966	979
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	4,581	4,294
Available-for-sale marketable securities, Unrealized Gain	34	46
Available-for-sale marketable securities, Unrealized (Loss)	(3)	(1)
Available-for-sale marketable securities, Fair Market Value	4,612	4,339
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,413	1,106
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	9,242	8,413
Available-for-sale marketable securities, Unrealized Gain	46	152
Available-for-sale marketable securities, Fair Market Value	9,288	8,565
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	619	625
Available-for-sale marketable securities, Fair Market Value	$ 619	$ 625

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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