Ownership Percentage

No definition available.

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- Definition

Ownership Percentage Upon Conversion of Preferred Shares

+ References

No definition available.

+ Details

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- Definition

Senior Secured Term Loan Receivable, Principal Outstanding

+ References

No definition available.

+ Details

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Balance Type:	debit
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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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Period Type:	instant

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

+ Details

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Balance Type:	na
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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.

+ References

No definition available.

+ Details

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- Details

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- Details

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Data Type:	na
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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=jef_HomeFedLLCMember
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- Details

Name:	srt_OwnershipAxis=jef_IdahoTimberMember
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- Details

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- Details

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- Details

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- Details

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Nature of Operations (Details) $ in Millions	6 Months Ended
Nature of Operations (Details) $ in Millions	May 31, 2020 USD ($) Segment	Jun. 30, 2019
HomeFed
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		70.00%
Vitesse Energy, LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	97.00%
JETX Energy
Schedule of Equity Method Investments [Line Items]
Ownership percentage	98.00%
HomeFed
Schedule of Equity Method Investments [Line Items]
Ownership percentage	100.00%
Idaho Timber
Schedule of Equity Method Investments [Line Items]
Ownership percentage	100.00%
Linkem
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	42.00%
Percentage of ownership upon conversion of preferred shares	56.00%
Investment in FXCM
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Senior secured term loan receivable, principal outstanding	$ 71.6
Jefferies Group
Schedule of Equity Method Investments [Line Items]
Number of business segments \| Segment	2
FXCM
Schedule of Equity Method Investments [Line Items]
Senior secured term loan receivable, principal outstanding	$ 71.6