Revenues from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
May 31, 2019	Jun. 30, 2018	May 31, 2019	Jun. 30, 2018	Nov. 30, 2018
Disaggregation of Revenue [Line Items]
Receivables related to revenue from contracts with customers	$ 289.9		$ 289.9		$ 250.6
Deferred revenue	21.0		21.0		14.2
Deferred revenue, revenue recognized	1.8	$ 9.6	9.4	$ 14.5
Capitalized contract cost	3.7		3.7		$ 4.7
Expenses related to capitalized costs to fulfill a contract	1.8	1.2	3.4	1.3
Jefferies Group
Disaggregation of Revenue [Line Items]
Revenue related to performance obligation satisfied	15.3	15.0	23.0	17.1
Revenue associated with distribution services, a portion of which related to prior period	$ 4.8	$ 4.3	$ 9.8	$ 8.9

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- Definition

Revenues Associated With Distribution Services

+ References

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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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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