Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 02, 2017	Jun. 03, 2017
Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 107,004	$ 138,450
Unrealized Gains	59	55
Unrealized Losses	35	43
Estimated Fair Value	107,028	138,462
Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,717	1,706
Unrealized Gains	792	753
Unrealized Losses	0	0
Estimated Fair Value	2,509	2,459
US government and agency obligations \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,906	20,259
Unrealized Gains	0	0
Unrealized Losses	34	43
Estimated Fair Value	20,872	20,216
Municipal bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,069	36,839
Unrealized Gains	31	34
Unrealized Losses	0	0
Estimated Fair Value	29,100	36,873
Corporate bonds \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	53,948	75,769
Unrealized Gains	28	21
Unrealized Losses	0	0
Estimated Fair Value	53,976	75,790
Asset backed securities \| Current investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,081	5,583
Unrealized Gains	0	0
Unrealized Losses	1	0
Estimated Fair Value	3,080	5,583
Mutual funds \| Noncurrent investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,717	1,706
Unrealized Gains	792	753
Unrealized Losses	0	0
Estimated Fair Value	$ 2,509	$ 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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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Name Accounting Standards Codification
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