Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 02, 2017	Jun. 03, 2017
Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 190,120	$ 138,450
Unrealized Gains	0	55
Unrealized Losses	628	43
Estimated Fair Value	189,492	138,462
Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,711	1,706
Unrealized Gains	936	753
Unrealized Losses	0	0
Estimated Fair Value	2,647	2,459
US government and agency obligations \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,907	20,259
Unrealized Gains	0	0
Unrealized Losses	120	43
Estimated Fair Value	20,787	20,216
Municipal bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	24,412	36,839
Unrealized Gains	0	34
Unrealized Losses	36	0
Estimated Fair Value	24,376	36,873
Corporate bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	139,274	75,769
Unrealized Gains	0	21
Unrealized Losses	467	0
Estimated Fair Value	138,807	75,790
Commercial paper \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,494
Unrealized Gains	0
Unrealized Losses	1
Estimated Fair Value	3,493
Asset backed securities \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,033	5,583
Unrealized Gains	0	0
Unrealized Losses	4	0
Estimated Fair Value	2,029	5,583
Mutual funds \| Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,711	1,706
Unrealized Gains	936	753
Unrealized Losses	0	0
Estimated Fair Value	$ 2,647	$ 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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