Investment Securities (Schedule of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 03, 2017	May 28, 2016
Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 138,450	$ 360,400
Gains in Accumulated Other Comprehensive Income	55	170
Losses in Accumulated Other Comprehensive Income	43	71
Estimated Fair Value	138,462	360,499
Noncurrent Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,706	1,448
Gains in Accumulated Other Comprehensive Income	753	489
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	2,459	1,937
US government and agency obligations \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,259	18,809
Gains in Accumulated Other Comprehensive Income	0	5
Losses in Accumulated Other Comprehensive Income	43	0
Estimated Fair Value	20,216	18,814
Municipal bonds \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	36,839	79,481
Gains in Accumulated Other Comprehensive Income	34	162
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	36,873	79,643
Corporate bonds \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	75,769	240,593
Gains in Accumulated Other Comprehensive Income	21	0
Losses in Accumulated Other Comprehensive Income	0	56
Estimated Fair Value	75,790	240,537
Asset backed securities \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,583	15,908
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	0	15
Estimated Fair Value	5,583	15,893
Mutual funds \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	3,565
Gains in Accumulated Other Comprehensive Income	0	1
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	0	3,566
Mutual funds \| Noncurrent Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,706	1,448
Gains in Accumulated Other Comprehensive Income	753	489
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	$ 2,459	1,937
Foreign government obligations \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		2,044
Gains in Accumulated Other Comprehensive Income		2
Losses in Accumulated Other Comprehensive Income		0
Estimated Fair Value		$ 2,046

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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