Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Oct. 03, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 328,741	$ 601,976
Available-for-sale marketable securities, Unrealized Gain	6,138	9,077
Available-for-sale marketable securities, Unrealized (Loss)	(594)	(213)
Available-for-sale marketable securities, Fair Market Value	334,285	610,840
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	63,447	70,418
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	80,370	257,132
Available-for-sale marketable securities, Unrealized Gain	636	1,330
Available-for-sale marketable securities, Unrealized (Loss)	(487)	(158)
Available-for-sale marketable securities, Fair Market Value	80,519	258,304
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	17,336	17,243
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	179,624	254,404
Available-for-sale marketable securities, Unrealized Gain	5	10
Available-for-sale marketable securities, Unrealized (Loss)	0	(1)
Available-for-sale marketable securities, Fair Market Value	179,629	254,413
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	20,799	12,173
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	53,329	76,129
Available-for-sale marketable securities, Unrealized Gain	5,421	7,539
Available-for-sale marketable securities, Unrealized (Loss)	(102)	(53)
Available-for-sale marketable securities, Fair Market Value	58,648	83,615
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	22,010	39,896
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	1,346	979
Available-for-sale marketable securities, Unrealized Gain	0
Available-for-sale marketable securities, Fair Market Value	1,346	979
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	4,610	4,294
Available-for-sale marketable securities, Unrealized Gain	11	46
Available-for-sale marketable securities, Unrealized (Loss)	(5)	(1)
Available-for-sale marketable securities, Fair Market Value	4,616	4,339
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	3,302	1,106
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	8,872	8,413
Available-for-sale marketable securities, Unrealized Gain	65	152
Available-for-sale marketable securities, Fair Market Value	8,937	8,565
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	590	625
Available-for-sale marketable securities, Fair Market Value	$ 590	$ 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=123581744&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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