Derivative Financial Instruments and Hedging Activities - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended												9 Months Ended
	Aug. 31, 2007	May 31, 2014	Aug. 31, 2013	Feb. 28, 2011 Interest rate swap Fair value hedging	Aug. 31, 2007 Interest rate swap Cash Flow Hedging	May 31, 2014 Forward contracts Forward foreign exchange contracts	Aug. 31, 2013 Forward contracts Forward foreign exchange contracts	May 31, 2014 Forward contracts Forward foreign exchange contracts Cash Flow Hedging	Aug. 31, 2013 Forward contracts Forward foreign exchange contracts Cash Flow Hedging	May 31, 2014 7.750% Senior Notes Due 2016	Aug. 31, 2013 7.750% Senior Notes Due 2016	Aug. 31, 2011 7.750% Senior Notes Due 2016	Feb. 28, 2011 7.750% Senior Notes Due 2016	May 31, 2014 8.250% Senior Notes Due 2018	Aug. 31, 2013 8.250% Senior Notes Due 2018	Aug. 31, 2007 8.250% Senior Notes Due 2018
Derivative [Line Items]
Aggregate notional amount outstanding				$ 200,000,000	$ 400,000,000	$ 899,000,000	$ 1,200,000,000	$ 429,400,000	$ 565,000,000
Amount estimated to reclassify into earnings during the next 12 months related to foreign currency risk management hedging arrangements		1,900,000
Senior unsecured notes, interest rate										7.75%	7.75%		7.75%	8.25%	8.25%	8.25%
Fair value of interest rate swap including accrued interest on interest rate swap												12,200,000
Accrued interest on interest rate swaps												600,000
Amortization of interest rate swaps		1,800,000
Hedge accounting adjustment related to terminated interest rate swaps		5,043,000	6,823,000
Payment to settle interest rate swaps	43,100,000
Expiry date														Mar. 15, 2018
Amount estimated to reclassify into earnings during the next 12 months related to interest rate risk management hedging arrangements		$ 4,000,000