Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 1,643,599
Translation adjustments	3,445
Impairment losses	(3,000)	$ 0
Goodwill, Ending Balance	1,644,044
Investment Banking and Capital Markets
Goodwill [Roll Forward]
Goodwill, Beginning Balance	1,640,201
Goodwill, Ending Balance	1,643,633
Asset Management
Goodwill [Roll Forward]
Goodwill, Beginning Balance	3,398
Goodwill, Ending Balance	$ 411

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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