Fair Value Reconciliation of Changes in Level 3 Balances (Details) - Auction Rate Securities [Member] - Fair Value, Measurements, Recurring [Member] $ in Millions	3 Months Ended
	May 26, 2017 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at the beginning of the period	$ 3.5
Balance at the end of period	3.5
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at the beginning of the period	3.5
Unrealized loss on investments	0.0
Balance at the end of period	$ 3.5