Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 28, 2025	Feb. 29, 2024	Nov. 30, 2024
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,827,938	$ 1,847,856
Currency translation and other adjustments	(3,291)	(231)
Measurement period adjustments		(26,954)
Goodwill reclassified as held for sale		3,366
Goodwill, ending balance	1,824,647	1,824,037
Goodwill	1,824,600		$ 1,827,900
Investment Banking and Capital Markets
Goodwill [Roll Forward]
Goodwill, beginning balance	1,533,013	1,532,172
Currency translation and other adjustments	(1,151)	(231)
Measurement period adjustments		0
Goodwill reclassified as held for sale		0
Goodwill, ending balance	1,531,862	1,531,941
Asset Management
Goodwill [Roll Forward]
Goodwill, beginning balance	294,925	315,684
Currency translation and other adjustments	(2,140)	0
Measurement period adjustments		(26,954)
Goodwill reclassified as held for sale		3,366
Goodwill, ending balance	292,785	$ 292,096
Goodwill	143,000		143,000
Investment banking
Goodwill [Roll Forward]
Goodwill	700,100		700,700
Equities and wealth management
Goodwill [Roll Forward]
Goodwill	255,200		255,400
Fixed income
Goodwill [Roll Forward]
Goodwill	576,500		576,900
Other investments
Goodwill [Roll Forward]
Goodwill	$ 149,800		$ 151,900

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