Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 03, 2018	Jun. 03, 2017
Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 178,494	$ 138,450
Unrealized Gains	0	55
Unrealized Losses	1,224	43
Estimated Fair Value	177,270	138,462
Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,023	1,706
Unrealized Gains	985	753
Unrealized Losses	0	0
Estimated Fair Value	3,008	2,459
US government and agency obligations \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	19,071	20,259
Unrealized Gains	0	0
Unrealized Losses	183	43
Estimated Fair Value	18,888	20,216
Municipal bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,188	36,839
Unrealized Gains	0	34
Unrealized Losses	23	0
Estimated Fair Value	21,165	36,873
Corporate bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	134,704	75,769
Unrealized Gains	0	21
Unrealized Losses	1,003	0
Estimated Fair Value	133,701	75,790
Certificates of deposits \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,504
Unrealized Gains	0
Unrealized Losses	0
Estimated Fair Value	1,504
Asset backed securities \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,027	5,583
Unrealized Gains	0	0
Unrealized Losses	15	0
Estimated Fair Value	2,012	5,583
Mutual funds \| Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,023	1,706
Unrealized Gains	985	753
Unrealized Losses	0	0
Estimated Fair Value	$ 3,008	$ 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
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