Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 01, 2018	Jun. 02, 2018
Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 273,531	$ 284,007
Unrealized Gains	0	0
Unrealized Losses	1,143	1,421
Estimated Fair Value	272,388	282,586
Noncurrent investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,051	2,037
Unrealized Gains	1,223	1,034
Unrealized Losses	0	0
Estimated Fair Value	3,274	3,071
US government and agency obligations \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,926	23,991
Unrealized Gains	0	0
Unrealized Losses	166	174
Estimated Fair Value	25,760	23,817
Municipal bonds \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	43,974	20,697
Unrealized Gains	0	0
Unrealized Losses	28	31
Estimated Fair Value	43,946	20,666
Commercial Paper [Member] \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,520	17,926
Unrealized Gains	0	0
Unrealized Losses	1	6
Estimated Fair Value	9,519	17,920
Corporate bonds \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	184,897	215,273
Unrealized Gains	0	0
Unrealized Losses	933	1,190
Estimated Fair Value	183,964	214,083
Certificates of deposits \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,509	2,510
Unrealized Gains	0	0
Unrealized Losses	2	3
Estimated Fair Value	2,507	2,507
Variable Rate Demand Obligation [Member] \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,700	600
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	3,700	600
Asset backed securities \| Current investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,005	3,010
Unrealized Gains	0	0
Unrealized Losses	13	17
Estimated Fair Value	2,992	2,993
Mutual funds \| Noncurrent investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,051	2,037
Unrealized Gains	1,223	1,034
Unrealized Losses	0	0
Estimated Fair Value	$ 3,274	$ 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

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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