Goodwill and Other Intangible Assets Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
Aug. 31, 2015	Nov. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 1,660,478	$ 1,662,636
Impairment losses	1,289
Exchange and clearing organization membership interests and registrations [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment losses	1,289
Investment Banking, Equities, and Fixed Income reporting units [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 1,657,500

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

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