Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Aug. 29, 2020	May 30, 2020
Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 148,665	$ 152,773
Unrealized Gains	1,859	1,390
Unrealized Losses	0	0
Estimated Fair Value	150,524	154,163
Noncurrent Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,019	2,005
Unrealized Gains	1,229	744
Unrealized Losses	0	0
Estimated Fair Value	3,248	2,749
Municipal bonds \| Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,255	16,093
Unrealized Gains	131	86
Unrealized Losses	0	0
Estimated Fair Value	16,386	16,179
Commercial paper \| Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,735	6,965
Unrealized Gains	2	17
Unrealized Losses	0	0
Estimated Fair Value	7,737	6,982
Corporate bonds \| Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	121,037	125,594
Unrealized Gains	1,704	1,274
Unrealized Losses	0	0
Estimated Fair Value	122,741	126,868
Certificates of deposits \| Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,002	1,492
Unrealized Gains	1	0
Unrealized Losses	0	0
Estimated Fair Value	1,003	1,492
Asset backed securities \| Current Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,636	2,629
Unrealized Gains	21	13
Unrealized Losses	0	0
Estimated Fair Value	2,657	2,642
Mutual funds \| Noncurrent Assets
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,019	2,005
Unrealized Gains	1,229	744
Unrealized Losses	0	0
Estimated Fair Value	$ 3,248	$ 2,749

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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