Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jul. 03, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 718,909	$ 745,498
Available-for-sale marketable securities, Unrealized Gain	6,286	2,145
Available-for-sale marketable securities, Unrealized (Loss)	(496)	(4,019)
Available-for-sale marketable securities, Fair Market Value	724,699	743,624
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	162,997	601,660
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	473,958	421,060
Available-for-sale marketable securities, Unrealized Gain	1,684	65
Available-for-sale marketable securities, Unrealized (Loss)	(11)	(1,167)
Available-for-sale marketable securities, Fair Market Value	475,631	419,958
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	118,777	379,434
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	140,995	163,297
Available-for-sale marketable securities, Unrealized Gain	3,060	902
Available-for-sale marketable securities, Unrealized (Loss)	(457)	(2,565)
Available-for-sale marketable securities, Fair Market Value	143,598	161,634
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	40,862	145,373
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	27,151	84,032
Available-for-sale marketable securities, Unrealized Gain	67	42
Available-for-sale marketable securities, Unrealized (Loss)		(122)
Available-for-sale marketable securities, Fair Market Value	27,218	83,952
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	2,421	55,120
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	27,958	43,391
Available-for-sale marketable securities, Unrealized Gain	16	6
Available-for-sale marketable securities, Unrealized (Loss)		(3)
Available-for-sale marketable securities, Fair Market Value	27,974	43,394
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		10,527
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	32,959	20,298
Available-for-sale marketable securities, Unrealized Gain	19	11
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	32,978	20,308
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		8,646
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	15,278	12,996
Available-for-sale marketable securities, Unrealized Gain	1,424	1,119
Available-for-sale marketable securities, Unrealized (Loss)	(28)	(161)
Available-for-sale marketable securities, Fair Market Value	16,674	13,954
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	937	2,560
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	610	424
Available-for-sale marketable securities, Unrealized Gain	16
Available-for-sale marketable securities, Fair Market Value	$ 626	$ 424

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

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