Investment Securities (Schedule of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 01, 2019	Jun. 02, 2018
Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 249,875	$ 284,007
Gains in Accumulated Other Comprehensive Income	315	0
Losses in Accumulated Other Comprehensive Income	9	1,421
Estimated Fair Value	250,181	282,586
Noncurrent Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,331	2,037
Gains in Accumulated Other Comprehensive Income	1,026	1,034
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	3,357	3,071
US government and agency obligations \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30,896	23,991
Gains in Accumulated Other Comprehensive Income	78	0
Losses in Accumulated Other Comprehensive Income	0	174
Estimated Fair Value	30,974	23,817
Municipal bonds \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	50,220	20,697
Gains in Accumulated Other Comprehensive Income	133	0
Losses in Accumulated Other Comprehensive Income	0	31
Estimated Fair Value	50,353	20,666
Certificates of deposits \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,149	2,510
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	1	3
Estimated Fair Value	6,148	2,507
Commercial paper \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,953	17,926
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	8	6
Estimated Fair Value	9,945	17,920
Corporate bonds \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	147,068	215,273
Gains in Accumulated Other Comprehensive Income	94	0
Losses in Accumulated Other Comprehensive Income	0	1,190
Estimated Fair Value	147,162	214,083
Variable rate demand notes \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	600
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	0	600
Asset backed securities \| Current Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,589	3,010
Gains in Accumulated Other Comprehensive Income	10	0
Losses in Accumulated Other Comprehensive Income	0	17
Estimated Fair Value	5,599	2,993
Mutual funds \| Noncurrent Investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,331	2,037
Gains in Accumulated Other Comprehensive Income	1,026	1,034
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	$ 3,357	$ 3,071

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

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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- Definition

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+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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