Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Apr. 02, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 1,156,716	$ 1,304,711
Available-for-sale marketable securities, Unrealized Gain	3,791	2,977
Available-for-sale marketable securities, Unrealized (Loss)	(2,868)	(2,821)
Available-for-sale marketable securities, Fair Market Value	1,157,639	1,304,867
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	990,454	732,979
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	856,714	901,975
Available-for-sale marketable securities, Unrealized Gain	37	97
Available-for-sale marketable securities, Unrealized (Loss)	(2,204)	(2,034)
Available-for-sale marketable securities, Fair Market Value	854,547	900,038
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	846,287	572,284
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	89,164	99,708
Available-for-sale marketable securities, Unrealized Gain	1,151	1,065
Available-for-sale marketable securities, Unrealized (Loss)	(584)	(620)
Available-for-sale marketable securities, Fair Market Value	89,731	100,153
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	56,678	53,642
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	21,174	42,026
Available-for-sale marketable securities, Unrealized Gain	8	7
Available-for-sale marketable securities, Unrealized (Loss)	(33)	(19)
Available-for-sale marketable securities, Fair Market Value	21,149	42,014
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	10,024	13,461
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	50,541	82,080
Available-for-sale marketable securities, Unrealized Gain	37	54
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	50,578	82,133
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		7,760
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	121,073	161,672
Available-for-sale marketable securities, Unrealized Gain	7	24
Available-for-sale marketable securities, Unrealized (Loss)	(15)	(66)
Available-for-sale marketable securities, Fair Market Value	121,065	161,630
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	76,050	84,034
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	17,472	16,505
Available-for-sale marketable securities, Unrealized Gain	2,546	1,724
Available-for-sale marketable securities, Unrealized (Loss)	(32)	(58)
Available-for-sale marketable securities, Fair Market Value	19,986	18,171
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,415	1,661
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	578	745
Available-for-sale marketable securities, Unrealized Gain	5	6
Available-for-sale marketable securities, Unrealized (Loss)		(23)
Available-for-sale marketable securities, Fair Market Value	$ 583	728
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		$ 137

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

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