Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Nov. 30, 2019
Income Taxes [Line Items]
Unrecognized tax benefits	$ 346,900		$ 327,300
Interest included in unrecognized tax benefits	70,700		67,200
Net deferred tax asset	447,200		462,500
Income tax provision	$ 45,773	$ 2,302
Effective income tax rate	29.00%	4.70%
Tax Cuts and Jobs Act of 2017, measurement period adjustment, income tax benefit		$ 6,700
Jefferies Group
Income Taxes [Line Items]
Unrecognized tax benefits	$ 208,100		$ 181,200

Income Taxes [Line Items]

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Tax Cuts And Jobs Act of 2017, Measurement Period Adjustment, Income Tax Expense (Benefit)

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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Amount of interest expense accrued for an underpayment of income taxes.

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