Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 28, 2026	Feb. 28, 2025	Nov. 30, 2025
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,837,570	$ 1,827,938
Currency translation and other adjustments	3,396	(3,291)
Impairment	(58,240)
Reclassification to held for sale	(56,850)
Goodwill, ending balance	1,725,876	1,824,647
Goodwill	1,725,900		$ 1,837,600
Investment Banking and Capital Markets
Goodwill [Roll Forward]
Goodwill, beginning balance	1,535,961	1,533,013
Currency translation and other adjustments	1,281	(1,151)
Impairment	0
Reclassification to held for sale	0
Goodwill, ending balance	1,537,242	1,531,862
Asset Management
Goodwill [Roll Forward]
Goodwill, beginning balance	301,609	294,925
Currency translation and other adjustments	2,115	(2,140)
Impairment	(58,240)
Reclassification to held for sale	(56,850)
Goodwill, ending balance	188,634	$ 292,785
Goodwill	143,000		143,000
Asset Management \| Discontinued Operations, Held-for-Sale
Goodwill [Roll Forward]
Impairment	(58,200)
Investment banking
Goodwill [Roll Forward]
Goodwill	702,600		702,000
Equities and wealth management
Goodwill [Roll Forward]
Goodwill	256,100		255,900
Fixed income
Goodwill [Roll Forward]
Goodwill	578,500		578,000
Other investments
Goodwill [Roll Forward]
Goodwill	$ 45,700		$ 158,700

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