Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Details) $ in Thousands	Feb. 28, 2021 USD ($) Contract	Nov. 30, 2020 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per consolidated statements of financial condition, assets	$ 529,923	$ 467,817
Net amounts per consolidated statements of financial condition, liabilities	1,084,938	641,065
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	1,188,274	560,810
Fair value, liabilities	1,223,227	565,390
Amounts offset in the consolidated statements of financial condition, assets	(1,137,116)	(546,989)
Amounts offset in the consolidated statements of financial condition, liabilities	(1,137,116)	(546,989)
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	484,790	109,456
Fair value, liabilities	374,473	147,713
Amounts offset in the consolidated statements of financial condition, assets	(372,819)	(109,228)
Amounts offset in the consolidated statements of financial condition, liabilities	(374,358)	(111,654)
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	1,461,466	1,353,687
Fair value, liabilities	2,484,341	1,726,621
Amounts offset in the consolidated statements of financial condition, assets	(1,094,672)	(899,919)
Amounts offset in the consolidated statements of financial condition, liabilities	(1,485,629)	(1,140,016)
Derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair value, assets	45,638	67,381
Fair value, liabilities	78,073	10,197
Derivatives designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 45,638	$ 67,381
Number of contracts, assets \| Contract	1	1
Fair value, liabilities	$ 32,653	$ 6,891
Number of contracts, liabilities \| Contract	1	1
Derivatives designated as accounting hedges \| Foreign exchange contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 0	$ 0
Number of contracts, assets \| Contract	0	0
Fair value, liabilities	$ 45,420	$ 3,306
Number of contracts, liabilities \| Contract	18	11
Derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 3,088,892	$ 1,956,572
Fair value, liabilities	4,003,968	2,429,527
Derivatives not designated as accounting hedges \| Interest rate contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 2,626	$ 2,442
Number of contracts, assets \| Contract	46,454	52,620
Fair value, liabilities	$ 2,305	$ 439
Number of contracts, liabilities \| Contract	16,056	42,611
Derivatives not designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 404,775	$ 17,379
Number of contracts, assets \| Contract	4,746	3,785
Fair value, liabilities	$ 305,691	$ 114,524
Number of contracts, liabilities \| Contract	4,364	4,307
Derivatives not designated as accounting hedges \| Interest rate contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 489,918	$ 626,210
Number of contracts, assets \| Contract	660	1,493
Fair value, liabilities	$ 450,254	$ 317,534
Number of contracts, liabilities \| Contract	1,491	466
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	0
Fair value, liabilities	$ 0	$ 0
Number of contracts, liabilities \| Contract	195	180
Derivatives not designated as accounting hedges \| Foreign exchange contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 470,949	$ 297,165
Number of contracts, assets \| Contract	18,733	15,005
Fair value, liabilities	$ 450,054	$ 277,628
Number of contracts, liabilities \| Contract	18,609	15,049
Derivatives not designated as accounting hedges \| Equity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 1,185,344	$ 558,304
Number of contracts, assets \| Contract	951,246	1,147,486
Fair value, liabilities	$ 1,220,922	$ 564,951
Number of contracts, liabilities \| Contract	845,486	971,938
Derivatives not designated as accounting hedges \| Equity contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 495,951	$ 429,304
Number of contracts, assets \| Contract	2,435	2,374
Fair value, liabilities	$ 1,529,978	$ 1,125,944
Number of contracts, liabilities \| Contract	2,487	2,421
Derivatives not designated as accounting hedges \| Commodity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 304	$ 64
Number of contracts, assets \| Contract	3,057	3,207
Fair value, liabilities	$ 0	$ 0
Number of contracts, liabilities \| Contract	2,070	2,654
Derivatives not designated as accounting hedges \| Commodity contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 0
Number of contracts, assets \| Contract	1
Fair value, liabilities	$ 0
Number of contracts, liabilities \| Contract	0
Derivatives not designated as accounting hedges \| Credit contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 34,377	$ 24,696
Number of contracts, assets \| Contract	80	39
Fair value, liabilities	$ 36,129	$ 26,298
Number of contracts, liabilities \| Contract	56	31
Derivatives not designated as accounting hedges \| Credit contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 4,648	$ 1,008
Number of contracts, assets \| Contract	13	11
Fair value, liabilities	$ 8,635	$ 2,209
Number of contracts, liabilities \| Contract	15	11

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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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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