Schedule of Available for Sale Marketable Securities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 29, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 847,486	$ 855,786
Available-for-sale marketable securities, Unrealized Gain	5,327	3,689
Available-for-sale marketable securities, Unrealized (Loss)	(297)	(1,515)
Available-for-sale marketable securities, Fair Market Value	852,516	857,960
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	104,322	241,760
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	227,889	202,573
Available-for-sale marketable securities, Unrealized Gain	202	75
Available-for-sale marketable securities, Unrealized (Loss)	(16)	(60)
Available-for-sale marketable securities, Fair Market Value	228,075	202,588
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	41,122	84,498
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	404,707	468,084
Available-for-sale marketable securities, Unrealized Gain	308	94
Available-for-sale marketable securities, Unrealized (Loss)	(73)	(283)
Available-for-sale marketable securities, Fair Market Value	404,942	467,895
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	36,402	108,212
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	108,446	105,583
Available-for-sale marketable securities, Unrealized Gain	13	16
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	108,459	105,598
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses		7,993
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	80,771	65,747
Available-for-sale marketable securities, Unrealized Gain	1,903	762
Available-for-sale marketable securities, Unrealized (Loss)	(184)	(1,122)
Available-for-sale marketable securities, Fair Market Value	82,490	65,387
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	25,959	40,355
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	11,567	10,463
Available-for-sale marketable securities, Unrealized Gain	2,898	2,742
Available-for-sale marketable securities, Unrealized (Loss)	(24)	(49)
Available-for-sale marketable securities, Fair Market Value	14,441	13,156
Available-for-sale marketable securities, Fair Market Value of Investment with Unrealized Losses	839	702
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	14,027	3,258
Available-for-sale marketable securities, Unrealized Gain	3
Available-for-sale marketable securities, Fair Market Value	14,030	3,258
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	79	78
Available-for-sale marketable securities, Fair Market Value	$ 79	$ 78