Investment Securities (Schedule of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 02, 2018	Jun. 03, 2017
Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 284,007	$ 138,450
Gains in Accumulated Other Comprehensive Income	0	55
Losses in Accumulated Other Comprehensive Income	1,421	43
Estimated Fair Value	282,586	138,462
Noncurrent Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,037	1,706
Gains in Accumulated Other Comprehensive Income	1,034	753
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	3,071	2,459
US government and agency obligations \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	23,991	20,259
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	174	43
Estimated Fair Value	23,817	20,216
Municipal bonds \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,697	36,839
Gains in Accumulated Other Comprehensive Income	0	34
Losses in Accumulated Other Comprehensive Income	31	0
Estimated Fair Value	20,666	36,873
Certificates of deposits \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,510
Gains in Accumulated Other Comprehensive Income	0
Losses in Accumulated Other Comprehensive Income	3
Estimated Fair Value	2,507
Commercial paper \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	17,926
Gains in Accumulated Other Comprehensive Income	0
Losses in Accumulated Other Comprehensive Income	6
Estimated Fair Value	17,920
Corporate bonds \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	215,273	75,769
Gains in Accumulated Other Comprehensive Income	0	21
Losses in Accumulated Other Comprehensive Income	1,190	0
Estimated Fair Value	214,083	75,790
Variable rate demand notes \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	600
Gains in Accumulated Other Comprehensive Income	0
Losses in Accumulated Other Comprehensive Income	0
Estimated Fair Value	600
Asset backed securities \| Current Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,010	5,583
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	17	0
Estimated Fair Value	2,993	5,583
Mutual funds \| Noncurrent Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,037	1,706
Gains in Accumulated Other Comprehensive Income	1,034	753
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	$ 3,071	$ 2,459

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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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