Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jul. 05, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 726,550	$ 1,000,625
Available-for-sale marketable securities, Unrealized Gain	3,572	4,818
Available-for-sale marketable securities, Unrealized (Loss)	(2,200)	(867)
Available-for-sale marketable securities, Fair Market Value	727,922	1,004,576
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	118,408	583,076
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	281,963	402,197
Available-for-sale marketable securities, Unrealized Gain	221	362
Available-for-sale marketable securities, Unrealized (Loss)	(662)	(405)
Available-for-sale marketable securities, Fair Market Value	281,522	402,154
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	21,403	317,771
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	183,601	258,452
Available-for-sale marketable securities, Unrealized Gain	170	135
Available-for-sale marketable securities, Unrealized (Loss)	(3)	(85)
Available-for-sale marketable securities, Fair Market Value	183,768	258,502
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	10,341	104,642
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	123,176	139,374
Available-for-sale marketable securities, Unrealized Gain	1,021	2,414
Available-for-sale marketable securities, Unrealized (Loss)	(1,501)	(321)
Available-for-sale marketable securities, Fair Market Value	122,696	141,467
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	61,348	96,998
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	48,438	140,616
Available-for-sale marketable securities, Unrealized Gain	10	26
Available-for-sale marketable securities, Unrealized (Loss)	(2)	(4)
Available-for-sale marketable securities, Fair Market Value	48,446	140,638
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	13,233	41,747
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	76,849	49,048
Available-for-sale marketable securities, Unrealized Gain	32	11
Available-for-sale marketable securities, Unrealized (Loss)	(5)	(23)
Available-for-sale marketable securities, Fair Market Value	76,876	49,036
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	11,009	20,684
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	12,083	10,492
Available-for-sale marketable securities, Unrealized Gain	2,118	1,870
Available-for-sale marketable securities, Unrealized (Loss)	(27)	(29)
Available-for-sale marketable securities, Fair Market Value	14,174	12,333
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,074	1,234
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	440	446
Available-for-sale marketable securities, Fair Market Value	$ 440	$ 446

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

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