CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019
Statement of Comprehensive Income [Abstract]
Currency translation adjustments and other, tax benefits (expenses)	$ 3.1	$ (7.4)
Changes in instrument specific credit risk, tax expense	7.9	6.0
Changes in instrument specific credit risk reclassified to Principal transactions revenues	(0.3)	0.3
Changes in instrument specific credit risk reclassified to Principal transactions revenues, tax benefits (expenses)	0.1	(0.1)
Cash flow hedges, tax benefit		0.1
Unrealized gain on available-for-sale securities, tax expense	$ 0.1	$ 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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- Definition

Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

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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://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=114867106&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: 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=114867106&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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