Fair Value Measurements - Fair Value Reconciliation Liabilities Using Significant Unobservable Inputs (Level 3) (Details) (Contingent Liability [Member], USD $) In Thousands, unless otherwise specified					3 Months Ended
	Nov. 30, 2013	Aug. 31, 2013	Nov. 30, 2012	Aug. 31, 2012	Nov. 30, 2013 Cost of Goods, Total	Nov. 30, 2012 Cost of Goods, Total
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance	$ 150,991	$ 134,134	$ 170,621	$ 127,516
Total gains or losses included in cost of goods sold and net interest					16,857	43,105
Balance	$ 150,991	$ 134,134	$ 170,621	$ 127,516