Investments and Fair Value Measurements-AFS FV and Unrealized Losses (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2014
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	$ 1,124,912
Less than 12 months, Gross Unrealized Loss	(3,197)
Greater than 12 months, Fair Value	294
Greater than 12 months, Gross Unrealized Loss	(4)
U.S. Treasury securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	126,006
Less than 12 months, Gross Unrealized Loss	(261)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
International Government Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	47,879
Less than 12 months, Gross Unrealized Loss	(200)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Corporate notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	414,858
Less than 12 months, Gross Unrealized Loss	(928)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Asset-backed securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	99,496
Less than 12 months, Gross Unrealized Loss	(239)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Mortgage-backed Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	46,368
Less than 12 months, Gross Unrealized Loss	(273)
Greater than 12 months, Fair Value	294
Greater than 12 months, Gross Unrealized Loss	(4)
Municipal notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	390,305
Less than 12 months, Gross Unrealized Loss	(1,296)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	$ 0