Investments and Fair Value Measurements (Details 3) (USD $) In Thousands	Oct. 02, 2011
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	$ 997,491
Less than 12 months, Gross Unrealized Loss	(5,124)
Greater than 12 months, Fair Value	12,634
Greater than 12 months, Gross Unrealized Loss	(47)
U.S. Treasury and government agency securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	63,863
Less than 12 months, Gross Unrealized Loss	(49)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
U.S. Government-sponsored agency securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	74,243
Less than 12 months, Gross Unrealized Loss	(20)
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	368,016
Less than 12 months, Gross Unrealized Loss	(3,721)
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	130,334
Less than 12 months, Gross Unrealized Loss	(98)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Municipal notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	361,035
Less than 12 months, Gross Unrealized Loss	(1,236)
Greater than 12 months, Fair Value	12,634
Greater than 12 months, Gross Unrealized Loss	$ (47)