Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Apr. 03, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 653,702	$ 745,498
Available-for-sale marketable securities, Unrealized Gain	3,897	2,145
Available-for-sale marketable securities, Unrealized (Loss)	(1,524)	(4,019)
Available-for-sale marketable securities, Fair Market Value	656,075	743,624
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	294,269	601,660
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	398,832	421,060
Available-for-sale marketable securities, Unrealized Gain	620	65
Available-for-sale marketable securities, Unrealized (Loss)	(175)	(1,167)
Available-for-sale marketable securities, Fair Market Value	399,277	419,958
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	204,136	379,434
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	161,005	163,297
Available-for-sale marketable securities, Unrealized Gain	1,861	902
Available-for-sale marketable securities, Unrealized (Loss)	(1,276)	(2,565)
Available-for-sale marketable securities, Fair Market Value	161,590	161,634
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	73,165	145,373
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	26,107	84,032
Available-for-sale marketable securities, Unrealized Gain	57	42
Available-for-sale marketable securities, Unrealized (Loss)	(4)	(122)
Available-for-sale marketable securities, Fair Market Value	26,160	83,952
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	9,747	55,120
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	15,651	43,391
Available-for-sale marketable securities, Unrealized Gain	2	6
Available-for-sale marketable securities, Unrealized (Loss)		(3)
Available-for-sale marketable securities, Fair Market Value	15,653	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	36,563	20,298
Available-for-sale marketable securities, Unrealized Gain	29	11
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	36,592	20,308
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	6,475	8,646
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	15,110	12,996
Available-for-sale marketable securities, Unrealized Gain	1,328	1,119
Available-for-sale marketable securities, Unrealized (Loss)	(69)	(161)
Available-for-sale marketable securities, Fair Market Value	16,369	13,954
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	746	2,560
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	434	424
Available-for-sale marketable securities, Fair Market Value	$ 434	$ 424

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

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