Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 29, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 286,073	$ 211,596
Available-for-sale marketable securities, Unrealized Gain	6,164	4,687
Available-for-sale marketable securities, Unrealized (Loss)	(1,187)	(262)
Available-for-sale marketable securities, Fair Market Value	291,050	216,021
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	42,283	23,999
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	82,680	42,167
Available-for-sale marketable securities, Unrealized Gain	2,958	431
Available-for-sale marketable securities, Unrealized (Loss)	(6)	(216)
Available-for-sale marketable securities, Fair Market Value	85,632	42,382
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	96	17,556
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	101,915	54,124
Available-for-sale marketable securities, Unrealized Gain	33	26
Available-for-sale marketable securities, Unrealized (Loss)	(1)	(1)
Available-for-sale marketable securities, Fair Market Value	101,947	54,149
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,296	1,391
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	65,696	93,267
Available-for-sale marketable securities, Unrealized Gain	2,951	4,081
Available-for-sale marketable securities, Unrealized (Loss)	(1,180)	(41)
Available-for-sale marketable securities, Fair Market Value	67,467	97,307
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	40,891	2,009
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	25,769	4,751
Available-for-sale marketable securities, Unrealized Gain	7
Available-for-sale marketable securities, Fair Market Value	25,776	4,751
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	4,335	9,942
Available-for-sale marketable securities, Unrealized Gain	67	14
Available-for-sale marketable securities, Unrealized (Loss)	0	(4)
Available-for-sale marketable securities, Fair Market Value	4,402	9,952
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	0	3,043
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	5,089	6,753
Available-for-sale marketable securities, Unrealized Gain	148	135
Available-for-sale marketable securities, Fair Market Value	5,237	6,888
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	589	592
Available-for-sale marketable securities, Fair Market Value	$ 589	$ 592

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=82897076&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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