Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Details) $ in Thousands	May 31, 2020 USD ($) Contract	Nov. 30, 2019 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 585,480	$ 397,551
Net amounts per Consolidated Statements of Financial Condition, Liabilities	417,703	527,205
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	422,892	718,685
Fair Value, Liabilities	502,252	962,638
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(409,622)	(688,871)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(409,622)	(688,871)
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	300,665	244,401
Fair Value, Liabilities	327,390	290,201
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(286,069)	(222,869)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(287,244)	(266,900)
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,390,263	867,271
Fair Value, Liabilities	1,270,944	906,153
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(832,649)	(521,066)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(986,017)	(676,016)
Derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair Value, Assets	74,227	28,663
Fair Value, Liabilities	0	0
Derivatives designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 74,227	$ 28,663
Number of Contracts, Assets \| Contract	1	1
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	0	0
Derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 2,039,593	$ 1,801,694
Fair Value, Liabilities	2,100,586	2,158,992
Derivatives not designated as accounting hedges \| Interest rate contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 515	$ 1,191
Number of Contracts, Assets \| Contract	43,775	65,226
Fair Value, Liabilities	$ 277	$ 103
Number of Contracts, Liabilities \| Contract	56,844	38,464
Derivatives not designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 226,248	$ 213,224
Number of Contracts, Assets \| Contract	4,332	3,329
Fair Value, Liabilities	$ 326,475	$ 284,433
Number of Contracts, Liabilities \| Contract	4,585	3,443
Derivatives not designated as accounting hedges \| Interest rate contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 732,046	$ 421,700
Number of Contracts, Assets \| Contract	1,244	1,325
Fair Value, Liabilities	$ 315,023	$ 258,857
Number of Contracts, Liabilities \| Contract	601	738
Derivatives not designated as accounting hedges \| Foreign exchange contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	0	256
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	139	199
Derivatives not designated as accounting hedges \| Foreign exchange contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 324,486	$ 190,570
Number of Contracts, Assets \| Contract	12,874	9,255
Fair Value, Liabilities	$ 341,814	$ 187,836
Number of Contracts, Liabilities \| Contract	12,669	9,187
Derivatives not designated as accounting hedges \| Equity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 422,377	$ 717,494
Number of Contracts, Assets \| Contract	986,001	1,714,538
Fair Value, Liabilities	$ 501,975	$ 962,535
Number of Contracts, Liabilities \| Contract	872,216	1,481,388
Derivatives not designated as accounting hedges \| Equity contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 330,034	$ 248,720
Number of Contracts, Assets \| Contract	1,398	4,731
Fair Value, Liabilities	$ 610,146	$ 445,241
Number of Contracts, Liabilities \| Contract	1,574	4,271
Derivatives not designated as accounting hedges \| Commodity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	3,251	5,524
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	4,572	4,646
Derivatives not designated as accounting hedges \| Credit contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 190	$ 2,514
Number of Contracts, Assets \| Contract	14	13
Fair Value, Liabilities	$ 915	$ 5,768
Number of Contracts, Liabilities \| Contract	6	12
Derivatives not designated as accounting hedges \| Credit contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,697	$ 6,281
Number of Contracts, Assets \| Contract	11	25
Fair Value, Liabilities	$ 3,961	$ 14,219
Number of Contracts, Liabilities \| Contract	7	28

The number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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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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The fair value as of the balance sheet date of firm holdings in all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments. Their value is derived from the values of one or more underlying assets, reference rates, or indices of asset values. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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Fair value of obligations arising from derivatives and other contracts sold short.

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