Derivative Financial Instruments - Unrealized and Realized Gains (Losses) on Derivative Contracts (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2013 Successor [Member]	May 31, 2013 Successor [Member] Interest rate contracts [Member]	May 31, 2013 Successor [Member] Foreign exchange contracts [Member]	May 31, 2013 Successor [Member] Equity contracts [Member]	May 31, 2013 Successor [Member] Commodity contracts [Member]	May 31, 2013 Successor [Member] Credit contracts [Member]	Feb. 28, 2013 Predecessor [Member]	May 31, 2012 Predecessor [Member]	May 31, 2012 Predecessor [Member]	Feb. 28, 2013 Predecessor [Member] Interest rate contracts [Member]	May 31, 2012 Predecessor [Member] Interest rate contracts [Member]	May 31, 2012 Predecessor [Member] Interest rate contracts [Member]	Feb. 28, 2013 Predecessor [Member] Foreign exchange contracts [Member]	May 31, 2012 Predecessor [Member] Foreign exchange contracts [Member]	May 31, 2012 Predecessor [Member] Foreign exchange contracts [Member]	Feb. 28, 2013 Predecessor [Member] Equity contracts [Member]	May 31, 2012 Predecessor [Member] Equity contracts [Member]	May 31, 2012 Predecessor [Member] Equity contracts [Member]	Feb. 28, 2013 Predecessor [Member] Commodity contracts [Member]	May 31, 2012 Predecessor [Member] Commodity contracts [Member]	May 31, 2012 Predecessor [Member] Commodity contracts [Member]	Feb. 28, 2013 Predecessor [Member] Credit contracts [Member]	May 31, 2012 Predecessor [Member] Credit contracts [Member]	May 31, 2012 Predecessor [Member] Credit contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized and realized gains (losses)	$ 77,911	$ 29,381	$ 4,135	$ 33,892	$ 21,513	$ (11,010)	$ 48,015	$ (17,829)	$ (57,562)	$ 25,713	$ (61,500)	$ (77,735)	$ 11,895	$ 7,648	$ 8,809	$ (5,436)	$ 4,351	$ (25,761)	$ 19,585	$ 25,832	$ 46,512	$ (3,742)	$ 5,840	$ (9,387)