Investment Securities (Schedule of Unrealized Holding Gain (Loss) on Investments) (Details) - USD ($) $ in Thousands	9 Months Ended
	Mar. 03, 2018	Feb. 25, 2017
Gain (Loss) on Investments [Line Items]
Unrealized holding gains, net of tax on available-for-sale securities	$ (664)	$ 124
Current investments
Gain (Loss) on Investments [Line Items]
Unrealized holding gains, net of tax on available-for-sale securities	(975)	(30)
Noncurrent investments
Gain (Loss) on Investments [Line Items]
Unrealized holding gains, net of tax on available-for-sale securities	$ 311	$ 154