Schedule of Available for Sale Marketable Securities (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 05, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 1,045,974	$ 1,000,625
Available-for-sale marketable securities, Unrealized Gain	6,297	4,818
Available-for-sale marketable securities, Unrealized (Loss)	(330)	(867)
Available-for-sale marketable securities, Fair Market Value	1,051,941us-gaap_AvailableForSaleSecurities	1,004,576us-gaap_AvailableForSaleSecurities
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	319,060	583,076
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	426,637	402,197
Available-for-sale marketable securities, Unrealized Gain	625	362
Available-for-sale marketable securities, Unrealized (Loss)	(143)	(405)
Available-for-sale marketable securities, Fair Market Value	427,119	402,154
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	217,722	317,771
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	231,747	258,452
Available-for-sale marketable securities, Unrealized Gain	443	135
Available-for-sale marketable securities, Unrealized (Loss)	(3)	(85)
Available-for-sale marketable securities, Fair Market Value	232,187	258,502
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	15,032	104,642
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	158,051	139,374
Available-for-sale marketable securities, Unrealized Gain	2,986	2,414
Available-for-sale marketable securities, Unrealized (Loss)	(160)	(321)
Available-for-sale marketable securities, Fair Market Value	160,877	141,467
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	51,495	96,998
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	130,227	140,616
Available-for-sale marketable securities, Unrealized Gain	72	26
Available-for-sale marketable securities, Unrealized (Loss)	(1)	(4)
Available-for-sale marketable securities, Fair Market Value	130,298	140,638
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	8,945	41,747
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	87,043	49,048
Available-for-sale marketable securities, Unrealized Gain	24	11
Available-for-sale marketable securities, Unrealized (Loss)	(15)	(23)
Available-for-sale marketable securities, Fair Market Value	87,052	49,036
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	25,705	20,684
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	11,823	10,492
Available-for-sale marketable securities, Unrealized Gain	2,147	1,870
Available-for-sale marketable securities, Unrealized (Loss)	(8)	(29)
Available-for-sale marketable securities, Fair Market Value	13,962	12,333
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	161	1,234
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	446	446
Available-for-sale marketable securities, Fair Market Value	$ 446	$ 446

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

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