Assets transferred due to securitization activities in which the Company had continuing involvement.

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- Definition

Beneficial interest in transfer of securitization assets.

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- Definition

Carrying amount of equity investments.

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- Definition

Carrying amount of variable interest in debt, equity and partnership interests that are eliminated in consolidation.

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- Definition

Commitment funded.

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- Definition

The fair value as of the balance sheet date of firm holdings in collateralized loan obligations in which are Variables Interest Entities.

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- Definition

Gain (loss) recognized on initial consolidation of collateralized loan obligations.

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- Definition

Maximum amount committed to make as per agreement.

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- Definition

Maximum equity investment.

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- Definition

Securitization Activities and Variable Interest Entities.

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- Definition

Servicing rights continued to be held by transferor fair value.

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph h
-Clause 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4/FIN46(R)-8
-Paragraph B11
-Subparagraph a
-Clause 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Cash flows between transferee and transferor in payment of the transferor's beneficial interest related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction.

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- Definition

A gain (loss) realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph h(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7,9)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

The amount of the support provided by the transferor with a continuing involvement that was not previously contractually required to provide to the transferee or its beneficial interest holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)(5)(i)
-URI http://asc.fasb.org/extlink&oid=6942082&loc=d3e107314-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4 and FIN46(R)-8
-Paragraph B11
-Subparagraph b
-Clause 1
-Subclause d(i)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

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Securitization Activities and Variable Interest Entities (Details Textuals) (USD $) In Millions	3 Months Ended			8 Months Ended	9 Months Ended
	Aug. 31, 2011	Nov. 30, 2010	Aug. 31, 2010	Aug. 31, 2010	Aug. 31, 2011	Aug. 31, 2011 Variable Interest Entity, Primary Beneficiary [Member]	Nov. 30, 2010 Variable Interest Entity, Primary Beneficiary [Member]	Jul. 26, 2010 Variable Interest Entity, Primary Beneficiary [Member]	Aug. 31, 2011 USA Fund [Member]	Nov. 30, 2010 USA Fund [Member]	Aug. 31, 2011 JEP IV [Member]	Nov. 30, 2010 JEP IV [Member]
Variable Interest Entity [Line Items]
Commitment funded						$ 17.9	$ 9.3				$ 43.6	$ 38.8
Carrying amount of equity investment									17.6	9.1	2.8	1.8
Carrying amount of debt securities of variable interest entities						12.4	8.8
Equity investment in Jefferies SBI USA Fund L.P. (the "USA Fund")								75.0
Securitization Activities and Variable Interest Entities (Textuals) [Abstract]
Additional financial support to securitization of vehicles	0	0			0
Assets transferred due to securitization	2,337.7		3,236.8	8,493.9	8,988.2
Cash proceeds from Transfer of securitization assets	1,922.7		2,710.7	6,982.0	7,421.1
Beneficial interest in Transfer of securitization assets	434.6		543.0	1,579.9	1,624.3
Servicing Rights in Transfer of securitization assets	0.3		0	0.1	0.3
Net revenues from Transfer of securitization assets	17.0		12.3	63.8	45.2
Beneficial interest held on projects	0				0
Carrying amount of variable interest as debt, equity and partnership interest	324.9	328.2			324.9
Gain (loss) recognized on initial consolidation of VIEs					0
Maximum amount committed to make as per agreement		$ 54.0