Long-Term Debt (Narrative) (Details)	3 Months Ended
Feb. 29, 2020 USD ($) Contract	Nov. 30, 2019 USD ($)
Structured notes \| Jefferies Group
Debt Instrument [Line Items]
Debt issued during period, principal amount, net of retirements	$ 136,200,000
Jefferies Group Revolving Credit Facility \| Jefferies Group
Debt Instrument [Line Items]
Debt principal amount	190,000,000.0
Bank loan obligations \| Jefferies Group
Debt Instrument [Line Items]
Debt principal amount	$ 50,000,000.0
Foursight Capital Credit Facilities
Debt Instrument [Line Items]
Number of warehouse credit commitments \| Contract	2
Maximum borrowing capacity	$ 175,000,000.0
Vitesse Energy Finance Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	170,000,000.0
Long-term debt, gross	$ 114,000,000.0	$ 104,000,000.0
Percentage of proved reserve value of oil and gas properties (minimum)	85.00%
LIBOR \| Bank loan obligations \| Jefferies Group
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Line of credit \| Foursight Capital Credit Facilities
Debt Instrument [Line Items]
Long-term debt, gross	$ 0.0	$ 98,700,000

Debt Instrument, Issued During Period, Principal Amount, Net Of Retirements

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- Definition

Line Of Credit Facility, Collateral, Percentage Of Proved Reserve Value of Oil and Gas Properties

+ References

No definition available.

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- Definition

Number of Warehouse Credit Commitments

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Face (par) amount of debt instrument at time of issuance.

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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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Publisher FASB
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