CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Feb. 28, 2021	Feb. 29, 2020
Statement of Comprehensive Income [Abstract]
Currency translation adjustments and other, tax benefits (expenses)	$ (3.2)	$ 3.1
Changes in instrument specific credit risk, tax benefits (expenses)	22.3	(7.9)
Changes in instrument specific credit risk reclassified to principal transactions revenues	(0.2)	(0.3)
Changes in instrument specific credit risk reclassified to principal transactions revenues, tax benefits (expenses)	$ 0.1	0.1
Unrealized gain on available-for-sale securities, tax expense		$ 0.1

Other Comprehensive Income (Loss) Changes In Instrument Specific Credit Risk Reclassified To Earnings, Tax

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- Definition

Other Comprehensive Income (Loss) Changes In Instrument Specific Credit Risk Reclassified To Earnings, Tax

+ References

No definition available.

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- Definition

Other Comprehensive Income (Loss), Changes in Instrument Specific Credit Risk, Tax

+ References

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32262-110900

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30755-110894

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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