Investments and Fair Value Measurements (Fair Value Level 3 Rollforward) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Nov. 30, 2013	Dec. 01, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 2,108	$ 9,074
Transfer to Level 2	0	(250)
Net change included in other comprehensive income	242	(1)
Sales	(2,350)	0
Balance at end of period	0	8,823
Proceeds from the sale of investments, at par	$ 2,350	$ 0