Investment Securities (Schedule of Investment Securities) (Details) - USD ($) $ in Thousands	May 30, 2020	Jun. 01, 2019
Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 152,773	$ 249,875
Gains in Accumulated Other Comprehensive Income	1,390	315
Losses in Accumulated Other Comprehensive Income	0	9
Estimated Fair Value	154,163	250,181
Noncurrent Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,005	2,331
Gains in Accumulated Other Comprehensive Income	744	1,026
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	2,749	3,357
US government and agency obligations \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		30,896
Gains in Accumulated Other Comprehensive Income		78
Losses in Accumulated Other Comprehensive Income		0
Estimated Fair Value		30,974
Municipal bonds \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,093	50,220
Gains in Accumulated Other Comprehensive Income	86	133
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	16,179	50,353
Commercial paper \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,492	6,149
Gains in Accumulated Other Comprehensive Income	0	0
Losses in Accumulated Other Comprehensive Income	0	1
Estimated Fair Value	1,492	6,148
Corporate bonds \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,965	9,953
Gains in Accumulated Other Comprehensive Income	17	0
Losses in Accumulated Other Comprehensive Income	0	8
Estimated Fair Value	6,982	9,945
Certificates of deposits \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	125,594	147,068
Gains in Accumulated Other Comprehensive Income	1,274	94
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	126,868	147,162
Asset backed securities \| Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,629	5,589
Gains in Accumulated Other Comprehensive Income	13	10
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	2,642	5,599
Mutual funds \| Noncurrent Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,005	2,331
Gains in Accumulated Other Comprehensive Income	744	1,026
Losses in Accumulated Other Comprehensive Income	0	0
Estimated Fair Value	$ 2,749	$ 3,357

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=121645371&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

No definition available.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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- Definition

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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