Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Detail) $ in Thousands	Nov. 30, 2017 USD ($) Contract	Nov. 30, 2016 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 163,833	$ 360,534
Net amounts per Consolidated Statements of Financial Condition, Liabilities	236,950	637,535
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,290,618	715,042
Fair Value, Liabilities	1,375,936	1,095,606
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,268,043)	(691,009)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,268,043)	(691,009)
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,340,384	2,836,457
Fair Value, Liabilities	1,275,027	2,638,773
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,319,895)	(2,751,650)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,274,900)	(2,638,774)
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	787,047	1,065,034
Fair Value, Liabilities	1,012,236	1,132,370
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(666,278)	(813,340)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(883,306)	(899,431)
Interest rate contracts \| Rule change by Chicago Mercantile Exchange
Derivatives, Fair Value [Line Items]
Amounts offset in the Consolidated Statements of Financial Condition, Assets		(1,000,000)
Derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair Value, Assets	0
Fair Value, Liabilities	2,420
Derivatives designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0
Number of Contracts, Assets \| Contract	0
Fair Value, Liabilities	$ 2,420
Number of Contracts, Liabilities \| Contract	1
Derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,418,049
Fair Value, Liabilities	3,660,779
Derivatives not designated as accounting hedges \| Interest rate contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,957	$ 2,275
Number of Contracts, Assets \| Contract	33,972	24,300
Fair Value, Liabilities	$ 66	$ 24
Number of Contracts, Liabilities \| Contract	8,515	29,773
Derivatives not designated as accounting hedges \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,334,878	$ 2,835,812
Number of Contracts, Assets \| Contract	2,711	3,596
Fair Value, Liabilities	$ 1,263,994	$ 2,636,469
Number of Contracts, Liabilities \| Contract	2,948	3,445
Derivatives not designated as accounting hedges \| Interest rate contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 380,223	$ 444,159
Number of Contracts, Assets \| Contract	1,804	1,136
Fair Value, Liabilities	$ 444,716	$ 522,965
Number of Contracts, Liabilities \| Contract	1,346	1,627
Derivatives not designated as accounting hedges \| Foreign exchange contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 157	$ 0
Number of Contracts, Assets \| Contract	2,045	376
Fair Value, Liabilities	$ 20	$ 0
Number of Contracts, Liabilities \| Contract	101	686
Derivatives not designated as accounting hedges \| Foreign exchange contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 303,091	$ 529,609
Number of Contracts, Assets \| Contract	4,338	7,448
Fair Value, Liabilities	$ 286,582	$ 516,869
Number of Contracts, Liabilities \| Contract	4,361	7,633
Derivatives not designated as accounting hedges \| Equity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,288,295	$ 712,767
Number of Contracts, Assets \| Contract	2,654,555	2,820,702
Fair Value, Liabilities	$ 1,375,832	$ 1,095,582
Number of Contracts, Liabilities \| Contract	2,090,935	2,410,956
Derivatives not designated as accounting hedges \| Equity contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 78,812	$ 72,041
Number of Contracts, Assets \| Contract	1,847	1,077
Fair Value, Liabilities	$ 247,750	$ 67,033
Number of Contracts, Liabilities \| Contract	1,722	1,191
Derivatives not designated as accounting hedges \| Commodity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 209	$ 0
Number of Contracts, Assets \| Contract	3,723	1,356
Fair Value, Liabilities	$ 18	$ 0
Number of Contracts, Liabilities \| Contract	3,819	920
Derivatives not designated as accounting hedges \| Credit contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 5,506	$ 645
Number of Contracts, Assets \| Contract	18	6
Fair Value, Liabilities	$ 8,613	$ 2,304
Number of Contracts, Liabilities \| Contract	27	8
Derivatives not designated as accounting hedges \| Credit contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 24,921	$ 19,225
Number of Contracts, Assets \| Contract	110	213
Fair Value, Liabilities	$ 33,188	$ 25,503
Number of Contracts, Liabilities \| Contract	164	184

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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