Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Detail) $ in Thousands	Aug. 31, 2015 USD ($) Contract	Nov. 30, 2014 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 468,823	$ 406,268
Net amounts per Consolidated Statements of Financial Condition, Liabilities	219,643	363,515
Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,287,955	1,075,642
Fair Value, Liabilities	1,150,569	1,040,076
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,146,698)	(1,038,992)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,146,698)	(1,038,992)
Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,973,526	1,443,206
Fair Value, Liabilities	1,953,948	1,504,593
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,924,391)	(1,416,613)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,924,391)	(1,416,613)
Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,602,289	2,646,765
Fair Value, Liabilities	1,619,648	2,675,464
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,323,858)	(2,303,740)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,433,433)	(2,401,013)
Interest rate contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,806	$ 2,450
Number of Contracts, Assets \| Contract	74,381	67,437
Fair Value, Liabilities	$ 1,930	$ 1,400
Number of Contracts, Liabilities \| Contract	104,483	87,008
Interest rate contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,930,070	$ 1,425,375
Number of Contracts, Assets \| Contract	3,195	2,160
Fair Value, Liabilities	$ 1,911,702	$ 1,481,329
Number of Contracts, Liabilities \| Contract	2,822	2,124
Interest rate contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 683,237	$ 871,982
Number of Contracts, Assets \| Contract	2,051	1,908
Fair Value, Liabilities	$ 613,344	$ 809,962
Number of Contracts, Liabilities \| Contract	898	729
Foreign exchange contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	419	1,562
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	407	1,821
Foreign exchange contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 777,346	$ 1,514,881
Number of Contracts, Assets \| Contract	10,234	11,299
Fair Value, Liabilities	$ 795,572	$ 1,519,349
Number of Contracts, Liabilities \| Contract	9,809	10,931
Equity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,286,149	$ 1,011,101
Number of Contracts, Assets \| Contract	3,082,363	2,269,044
Fair Value, Liabilities	$ 1,148,639	$ 987,531
Number of Contracts, Liabilities \| Contract	3,082,310	2,049,513
Equity contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 88,463	$ 39,889
Number of Contracts, Assets \| Contract	1,017	2,463
Fair Value, Liabilities	$ 143,041	$ 70,484
Number of Contracts, Liabilities \| Contract	967	1,956
Commodity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 62,091
Number of Contracts, Assets \| Contract	253,123	1,027,542
Fair Value, Liabilities	$ 0	$ 51,145
Number of Contracts, Liabilities \| Contract	252,949	1,015,894
Commodity contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 38,418	$ 214,635
Number of Contracts, Assets \| Contract	488	4,026
Fair Value, Liabilities	$ 23,161	$ 252,061
Number of Contracts, Liabilities \| Contract	544	4,524
Credit contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 43,456	$ 17,831
Number of Contracts, Assets \| Contract	103	27
Fair Value, Liabilities	$ 42,246	$ 23,264
Number of Contracts, Liabilities \| Contract	88	22
Credit contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 14,825	$ 5,378
Number of Contracts, Assets \| Contract	93	18
Fair Value, Liabilities	$ 44,530	$ 23,608
Number of Contracts, Liabilities \| Contract	99	27

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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