Compensation Plans - Compensation Cost (Details) - USD ($) $ in Millions	12 Months Ended
Nov. 30, 2022	Nov. 30, 2021	Nov. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense	$ 251.0	$ 461.5	$ 522.1
Profit sharing plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense	10.5	7.8	7.8
Restricted cash awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense	196.6	375.5	474.3
Accelerated amortization	0.0	188.3
Stock options and Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense	0.0	48.7	0.1
Restricted stock and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense	43.9	29.5	39.9
Restricted stock and RSUs \| Deferred Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted cash awards	$ 0.5	$ 0.4	$ 0.3

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
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