Investments and Fair Value Measurements-AFS Investments (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 29, 2013	Dec. 30, 2012
Fixed Income Securities [Member]
Available-for-sale investments
Amortized Cost	$ 5,128,833	$ 4,920,082
Gross Unrealized Gain	20,599	27,111
Gross Unrealized Loss	(4,179)	(1,868)
Fair Value	5,145,253	4,945,325
U.S. Treasury and government agency securities [Member]
Available-for-sale investments
Amortized Cost	160,598	27,377
Gross Unrealized Gain	21	9
Gross Unrealized Loss	(424)	0
Fair Value	160,195	27,386
U.S. Government-sponsored agency securities [Member]
Available-for-sale investments
Amortized Cost	8,112	28,339
Gross Unrealized Gain	10	41
Gross Unrealized Loss	(1)	(1)
Fair Value	8,121	28,379
International Government Securities [Member]
Available-for-sale investments
Amortized Cost	38,492	153,936
Gross Unrealized Gain	1	13
Gross Unrealized Loss	(224)	(3)
Fair Value	38,269	153,946
Corporate notes and bonds [Member]
Available-for-sale investments
Amortized Cost	864,331	864,170
Gross Unrealized Gain	1,504	3,890
Gross Unrealized Loss	(1,565)	(938)
Fair Value	864,270	867,122
Asset-backed securities [Member]
Available-for-sale investments
Amortized Cost	226,620	179,356
Gross Unrealized Gain	114	453
Gross Unrealized Loss	(170)	0
Fair Value	226,564	179,809
Mortgage-backed securities [Member]
Available-for-sale investments
Amortized Cost	86,542	1,872
Gross Unrealized Gain	18	8
Gross Unrealized Loss	(554)	(14)
Fair Value	86,006	1,866
Municipal notes and bonds [Member]
Available-for-sale investments
Amortized Cost	3,744,138	3,665,032
Gross Unrealized Gain	18,931	22,697
Gross Unrealized Loss	(1,241)	(912)
Fair Value	$ 3,761,828	$ 3,686,817