Goodwill and Other Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	May 31, 2018	Nov. 30, 2017
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Table] [Line Items]
Total gross costs - intangible assets	$ 263,772	$ 264,333
Accumulated amortization - finite lived intangible assets	(74,391)	(68,540)
Total net carrying amount - intangible assets	189,381	195,793
Exchange and clearing organization membership interests and registrations
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Table] [Line Items]
Gross costs - indefinite lived intangible assets	8,550	8,551
Net carrying amount - indefinite lived intangible assets	8,550	8,551
Customer relationships
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Table] [Line Items]
Gross costs - finite lived intangible assets	126,170	126,412
Accumulated amortization - finite lived intangible assets	(55,033)	(50,983)
Net carrying amount - finite lived intangible assets	$ 71,137	$ 75,429
Weighted average remaining lives (years)	10 years 11 months	11 years 3 months
Trade name
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Table] [Line Items]
Gross costs - finite lived intangible assets	$ 129,052	$ 129,370
Accumulated amortization - finite lived intangible assets	(19,358)	(17,557)
Net carrying amount - finite lived intangible assets	$ 109,694	$ 111,813
Weighted average remaining lives (years)	29 years 9 months	30 years 3 months