Income Taxes - Rollforward of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balances	$ 72,181	$ 67,271	$ 67,271
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	0	35,718	0
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	0	(9,867)	0
Reductions attributable to statute expiration	0	(20,941)	0
Balances at August 31	$ 72,181	$ 72,181	$ 67,271