Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Details) $ in Thousands	Nov. 30, 2020 USD ($) Contract	Nov. 30, 2019 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per consolidated statements of financial condition, assets	$ 467,817	$ 397,551
Net amounts per consolidated statements of financial condition, liabilities	641,065	527,205
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	560,810	718,685
Fair value, liabilities	565,390	962,638
Amounts offset in the consolidated statements of financial condition, assets	(546,989)	(688,871)
Amounts offset in the consolidated statements of financial condition, liabilities	(546,989)	(688,871)
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	109,456	244,401
Fair value, liabilities	147,713	290,201
Amounts offset in the consolidated statements of financial condition, assets	(109,228)	(222,869)
Amounts offset in the consolidated statements of financial condition, liabilities	(111,654)	(266,900)
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	1,353,687	867,271
Fair value, liabilities	1,726,621	906,153
Amounts offset in the consolidated statements of financial condition, assets	(899,919)	(521,066)
Amounts offset in the consolidated statements of financial condition, liabilities	(1,140,016)	(676,016)
Derivatives designated as accounting hedges:
Derivatives, Fair Value [Line Items]
Fair value, assets	67,381	28,663
Fair value, liabilities	10,197	0
Derivatives designated as accounting hedges: \| Interest rate contracts: \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 67,381	$ 28,663
Number of contracts, assets \| Contract	1	1
Fair value, liabilities	$ 6,891	$ 0
Number of contracts, liabilities \| Contract	1	0
Derivatives designated as accounting hedges: \| Foreign exchange contracts: \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 0
Number of contracts, assets \| Contract	0
Fair value, liabilities	$ 3,306
Number of contracts, liabilities \| Contract	11
Derivatives not designated as accounting hedges:
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 1,956,572	$ 1,801,694
Fair value, liabilities	2,429,527	2,158,992
Derivatives not designated as accounting hedges: \| Interest rate contracts: \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 2,442	$ 1,191
Number of contracts, assets \| Contract	52,620	65,226
Fair value, liabilities	$ 439	$ 103
Number of contracts, liabilities \| Contract	42,611	38,464
Derivatives not designated as accounting hedges: \| Interest rate contracts: \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 17,379	$ 213,224
Number of contracts, assets \| Contract	3,785	3,329
Fair value, liabilities	$ 114,524	$ 284,433
Number of contracts, liabilities \| Contract	4,307	3,443
Derivatives not designated as accounting hedges: \| Interest rate contracts: \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 626,210	$ 421,700
Number of contracts, assets \| Contract	1,493	1,325
Fair value, liabilities	$ 317,534	$ 258,857
Number of contracts, liabilities \| Contract	466	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	180	199
Derivatives not designated as accounting hedges: \| Foreign exchange contracts: \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 297,165	$ 190,570
Number of contracts, assets \| Contract	15,005	9,255
Fair value, liabilities	$ 277,628	$ 187,836
Number of contracts, liabilities \| Contract	15,049	9,187
Derivatives not designated as accounting hedges: \| Equity contracts: \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 558,304	$ 717,494
Number of contracts, assets \| Contract	1,147,486	1,714,538
Fair value, liabilities	$ 564,951	$ 962,535
Number of contracts, liabilities \| Contract	971,938	1,481,388
Derivatives not designated as accounting hedges: \| Equity contracts: \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 429,304	$ 248,720
Number of contracts, assets \| Contract	2,374	4,731
Fair value, liabilities	$ 1,125,944	$ 445,241
Number of contracts, liabilities \| Contract	2,421	4,271
Derivatives not designated as accounting hedges: \| Commodity contracts: \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 64	$ 0
Number of contracts, assets \| Contract	3,207	5,524
Fair value, liabilities	$ 0	$ 0
Number of contracts, liabilities \| Contract	2,654	4,646
Derivatives not designated as accounting hedges: \| Credit contracts: \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 24,696	$ 2,514
Number of contracts, assets \| Contract	39	13
Fair value, liabilities	$ 26,298	$ 5,768
Number of contracts, liabilities \| Contract	31	12
Derivatives not designated as accounting hedges: \| Credit contracts: \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair value, assets	$ 1,008	$ 6,281
Number of contracts, assets \| Contract	11	25
Fair value, liabilities	$ 2,209	$ 14,219
Number of contracts, liabilities \| Contract	11	28

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

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