Derivative Financial Instruments and Hedging Activities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Aug. 31, 2007	May. 31, 2015	Aug. 31, 2014	Aug. 31, 2011	Feb. 28, 2011
Derivative [Line Items]
Amortization of interest rate swaps		$ 1,800
Hedge accounting adjustment related to terminated interest rate swaps		2,670	$ 4,450
Payment to settle interest rate swaps	$ 43,100
Interest rate swap | Fair value hedging
Derivative [Line Items]
Aggregate notional amount outstanding					$ 200,000
Interest rate swap | Cash Flow Hedging
Derivative [Line Items]
Aggregate notional amount outstanding	$ 400,000
Forward foreign exchange contracts
Derivative [Line Items]
Aggregate notional amount outstanding		1,400,000	1,200,000
Forward foreign exchange contracts | Cash Flow Hedging
Derivative [Line Items]
Aggregate notional amount outstanding		$ 429,500	$ 626,900
7.750% Senior Notes Due 2016
Derivative [Line Items]
Fair value of interest rate swap including accrued interest on interest rate swap				$ 12,200
Accrued interest on interest rate swaps				$ 600