Investments (Schedule of Investment Securities, Aggregated by Investment Type and Length of Time) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 26, 2011	Jun. 27, 2010
Fair Value, Less than 12 Months	$ 41,350	$ 143,817
Unrealized Loss, Less than 12 Months	(127)	(181)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total	41,350	143,817
Unrealized Loss, Total	(127)	(181)
Number of securities with an unrealized loss	20	42
Municipal Bonds [Member]
Fair Value, Less than 12 Months	14,348	117,470
Unrealized Loss, Less than 12 Months	(10)	(117)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total	14,348	117,470
Unrealized Loss, Total	(10)	(117)
Corporate Bonds [Member]
Fair Value, Less than 12 Months	20,484	11,126
Unrealized Loss, Less than 12 Months	(115)	(20)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total	20,484	11,126
Unrealized Loss, Total	(115)	(20)
Municipal Variable Rate Demand Notes [Member]
Fair Value, Less than 12 Months		5,006
Unrealized Loss, Less than 12 Months		(1)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total		5,006
Unrealized Loss, Total		(1)
Certificates of Deposit [Member]
Fair Value, Less than 12 Months
Unrealized Loss, Less than 12 Months
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total
Unrealized Loss, Total
Commercial Paper [Member]
Fair Value, Less than 12 Months
Unrealized Loss, Less than 12 Months
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total
Unrealized Loss, Total
U.S. Agency Securities [Member]
Fair Value, Less than 12 Months	6,518	5,120
Unrealized Loss, Less than 12 Months	(2)	(32)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total	6,518	5,120
Unrealized Loss, Total	(2)	(32)
U.S. Government Securities [Member]
Fair Value, Less than 12 Months
Unrealized Loss, Less than 12 Months
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total
Unrealized Loss, Total
Non-U.S. Government Securities [Member]
Fair Value, Less than 12 Months		5,095
Unrealized Loss, Less than 12 Months		(11)
Fair Value, Greater than 12 Months
Unrealized Loss, Greater than 12 Months
Fair Value, Total		5,095
Unrealized Loss, Total		$ (11)
Less than 12 Months [Member]
Number of securities with an unrealized loss	20	42
Greater than 12 Months [Member]
Number of securities with an unrealized loss