Goodwill and Other Intangible Assets - Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			3 Months Ended		12 Months Ended
	May 31, 2012	May 31, 2013 Successor [Member]	May 31, 2013 Successor [Member] Exchange and clearing organization membership interests and registrations [Member]	May 31, 2013 Successor [Member] Customer relationships [Member]	May 31, 2013 Successor [Member] Trade names (intangible assets) [Member]	Nov. 30, 2012 Predecessor [Member]	Nov. 30, 2012 Predecessor [Member] Exchange and clearing organization membership interests and registrations [Member]	Nov. 30, 2012 Predecessor [Member] Customer relationships [Member]	Nov. 30, 2012 Predecessor [Member] Trade names (intangible assets) [Member]	Nov. 30, 2012 Predecessor [Member] Other intangible assets [Member]
Gross cost				$ 136,002	$ 131,299			$ 10,542	$ 1,680	$ 100
Gross cost			16,060				11,219
Gross cost		283,361				23,541
Impairment losses	(2,900)					(2,873)	(2,873)
Accumulated amortization		(6,588)		(5,650)	(938)	(5,409)		(4,107)	(1,287)	(15)
Net carrying amount				130,352	130,361			6,435	393	85
Net carrying amount			16,060				8,346
Net carrying amount		$ 276,773				$ 15,259
Weighted average remaining lives (years)				14 years 4 months 24 days	34 years 9 months 18 days		7 years 10 months 24 days	7 years 10 months 24 days	3 years 6 months	12 years 9 months 18 days