Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Apr. 01, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 929,385	$ 1,470,729
Available-for-sale marketable securities, Unrealized Gain	1,240	6,582
Available-for-sale marketable securities, Unrealized (Loss)	(3,453)	(3,406)
Available-for-sale marketable securities, Fair Market Value	927,172	1,473,905
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	890,956	1,350,896
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	614,365	858,258
Available-for-sale marketable securities, Unrealized Gain	19	72
Available-for-sale marketable securities, Unrealized (Loss)	(2,438)	(2,535)
Available-for-sale marketable securities, Fair Market Value	611,946	855,795
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	610,938	850,163
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	252,579	283,009
Available-for-sale marketable securities, Unrealized Gain	17	18
Available-for-sale marketable securities, Unrealized (Loss)	(438)	(187)
Available-for-sale marketable securities, Fair Market Value	252,158	282,840
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	249,871	258,933
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	43,472	131,179
Available-for-sale marketable securities, Unrealized Gain	1,200	2,380
Available-for-sale marketable securities, Unrealized (Loss)	(454)	(373)
Available-for-sale marketable securities, Fair Market Value	44,218	133,186
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	17,742	91,010
Equity and Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost		19,403
Available-for-sale marketable securities, Unrealized Gain		4,102
Available-for-sale marketable securities, Unrealized (Loss)		(75)
Available-for-sale marketable securities, Fair Market Value		23,430
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		1,723
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	10,791	10,775
Available-for-sale marketable securities, Unrealized (Loss)	(65)	(49)
Available-for-sale marketable securities, Fair Market Value	10,726	10,726
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	10,726	10,726
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	4,820	167,523
Available-for-sale marketable securities, Unrealized Gain	4	6
Available-for-sale marketable securities, Unrealized (Loss)		(187)
Available-for-sale marketable securities, Fair Market Value	4,824	167,342
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		138,340
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	559	582
Available-for-sale marketable securities, Unrealized Gain		4
Available-for-sale marketable securities, Fair Market Value	559	$ 586
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	2,799
Available-for-sale marketable securities, Unrealized (Loss)	(58)
Available-for-sale marketable securities, Fair Market Value	2,741
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 1,679

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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