Aggregate equity commitment.

No definition available.

Name:	jef_AggregateEquityCommitment
Namespace Prefix:	jef_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Earned Placement Fees

+ References

No definition available.

+ Details

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Namespace Prefix:	jef_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Equity commitment.

+ References

No definition available.

+ Details

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Namespace Prefix:	jef_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of revenue from providing administrative services, including, but not limited to, accounting, tax, legal, regulatory filing, and share registration activities of managed funds and investment accounts of independent third parties and related and affiliated entities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

+ References

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

-Publisher FASB

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-Section S99

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-Subparagraph (SX 210.4-08.(k)(1))

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-Publisher SEC

-Name Regulation S-X (SX)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Publisher FASB

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-Subparagraph (SX 210.7-03.3)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10(3))

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Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of net income (loss) reported by an equity method investment of the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(g))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph bb

-Article 1

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-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph g

-Subparagraph 1, 2

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph w

-Article 1

+ Details

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Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=jef_JefferiesLoanCoreLlcMember
Namespace Prefix:
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Investments - Jefferies LoanCore - Narrative (Detail) (USD $)	3 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Nov. 30, 2014	Feb. 23, 2011
Guarantee Obligations [Line Items]
Equity commitment	$ 600,000,000jef_EquityCommitment
Jefferies LoanCore, LLC [Member]
Guarantee Obligations [Line Items]
Aggregate commitment				600,000,000
Funded portion of equity commitment to subsidiary	237,000,000	200,900,000
Equity commitment	291,000,000
Percentage of the Variable Interest Entity's (VIE) voting interest	48.50%
Net earnings from equity method investment	20,000,000	5,000,000
Reimbursed administrative services	47,400	100,000
Receivables under service agreement	15,800		8,900
Placement fees earned	$ 400,000	$ 300,000