Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Oct. 01, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 1,425,947	$ 1,304,711
Available-for-sale marketable securities, Unrealized Gain	6,100	2,977
Available-for-sale marketable securities, Unrealized (Loss)	(2,274)	(2,821)
Available-for-sale marketable securities, Fair Market Value	1,429,773	1,304,867
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,243,640	732,979
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	944,120	904,737
Available-for-sale marketable securities, Unrealized Gain	64	97
Available-for-sale marketable securities, Unrealized (Loss)	(1,934)	(2,034)
Available-for-sale marketable securities, Fair Market Value	942,250	902,800
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	936,195	572,284
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	116,687	99,708
Available-for-sale marketable securities, Unrealized Gain	2,046	1,065
Available-for-sale marketable securities, Unrealized (Loss)	(246)	(620)
Available-for-sale marketable securities, Fair Market Value	118,487	100,153
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	79,119	53,642
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	55,936	39,264
Available-for-sale marketable securities, Unrealized Gain	20	7
Available-for-sale marketable securities, Unrealized (Loss)	(18)	(19)
Available-for-sale marketable securities, Fair Market Value	55,938	39,252
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	52,997	13,461
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	95,447	82,080
Available-for-sale marketable securities, Unrealized Gain	29	54
Available-for-sale marketable securities, Unrealized (Loss)	(7)	(1)
Available-for-sale marketable securities, Fair Market Value	95,469	82,133
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	33,238	7,760
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	194,985	161,672
Available-for-sale marketable securities, Unrealized Gain	11	24
Available-for-sale marketable securities, Unrealized (Loss)	(48)	(66)
Available-for-sale marketable securities, Fair Market Value	194,948	161,630
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	140,562	84,034
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	18,202	16,505
Available-for-sale marketable securities, Unrealized Gain	3,923	1,724
Available-for-sale marketable securities, Unrealized (Loss)	(21)	(58)
Available-for-sale marketable securities, Fair Market Value	22,104	18,171
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,529	1,661
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	570	745
Available-for-sale marketable securities, Unrealized Gain	7	6
Available-for-sale marketable securities, Unrealized (Loss)		(23)
Available-for-sale marketable securities, Fair Market Value	$ 577	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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