Available-For-Sale Securities - Classified As Current Assets (Schedule Of Available-For-Sale Securities Classified As Current Assets) (Details) (USD $) In Thousands, unless otherwise specified	May 31, 2014		Jun. 01, 2013
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value	$ 196,189
Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	194,434		157,847
Gains in Accumulated Other Comprehensive Income	304		81
Losses in Accumulated Other Comprehensive Income			24
Estimated Fair Value	194,738		157,904
Noncurrent Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	999		721
Gains in Accumulated Other Comprehensive Income	452		305
Estimated Fair Value	1,451		1,026
State Municipal Bonds [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	75,659		61,124
Gains in Accumulated Other Comprehensive Income	188		71
Estimated Fair Value	75,847		61,195
US Government Obligations [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,056		12,378
Gains in Accumulated Other Comprehensive Income	5
Losses in Accumulated Other Comprehensive Income			1
Estimated Fair Value	4,061		12,377
Corporate Bonds [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	102,587		64,406
Gains in Accumulated Other Comprehensive Income	98
Losses in Accumulated Other Comprehensive Income			23
Estimated Fair Value	102,685		64,383
Commercial Paper [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,927
Gains in Accumulated Other Comprehensive Income	3
Estimated Fair Value	3,930
Certificates Of Deposit [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	350		12,280
Gains in Accumulated Other Comprehensive Income	1		5
Estimated Fair Value	351		12,285
Variable Rate Demand Notes [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,000
Estimated Fair Value	2,000
Government Agency Bonds [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,791		7,659
Gains in Accumulated Other Comprehensive Income	7		5
Estimated Fair Value	4,798		7,664
Foreign Government Obligations [Member] | Current Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,064
Gains in Accumulated Other Comprehensive Income	2
Estimated Fair Value	1,066
Mutual Funds [Member] | Noncurrent Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	999	[1]	721	[1]
Gains in Accumulated Other Comprehensive Income	452	[1]	305	[1]
Estimated Fair Value	$ 1,451	[1]	$ 1,026	[1]

[1] The mutual funds are classified as long term and are a part of “other investments” in the Consolidated Balance Sheet.