Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Detail) $ in Thousands	Feb. 29, 2016 USD ($) Contract	Nov. 30, 2015 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 332,068	$ 251,080
Net amounts per Consolidated Statements of Financial Condition, Liabilities	326,619	208,548
Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	807,271	956,285
Fair Value, Liabilities	927,408	1,005,063
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(775,729)	(938,482)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(775,729)	(938,482)
Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	3,936,358	2,214,351
Fair Value, Liabilities	3,947,267	2,203,677
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(3,906,560)	(2,184,438)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(3,906,560)	(2,184,438)
Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,439,242	1,245,890
Fair Value, Liabilities	1,331,134	1,257,806
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,168,514)	(1,042,526)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,196,901)	(1,135,078)
Interest rate contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 517	$ 998
Number of Contracts, Assets \| Contract	37,308	52,605
Fair Value, Liabilities	$ 157	$ 364
Number of Contracts, Liabilities \| Contract	57,663	70,672
Interest rate contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,935,958	$ 2,213,730
Number of Contracts, Assets \| Contract	2,978	2,742
Fair Value, Liabilities	$ 3,946,991	$ 2,202,836
Number of Contracts, Liabilities \| Contract	2,943	2,869
Interest rate contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 851,824	$ 695,365
Number of Contracts, Assets \| Contract	2,068	1,401
Fair Value, Liabilities	$ 727,533	$ 646,758
Number of Contracts, Liabilities \| Contract	683	1,363
Foreign exchange contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	480	441
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	436	112
Foreign exchange contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 466,668	$ 453,202
Number of Contracts, Assets \| Contract	10,332	7,646
Fair Value, Liabilities	$ 477,380	$ 466,021
Number of Contracts, Liabilities \| Contract	9,520	7,264
Equity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 806,754	$ 955,287
Number of Contracts, Assets \| Contract	2,604,349	3,054,315
Fair Value, Liabilities	$ 927,251	$ 1,004,699
Number of Contracts, Liabilities \| Contract	2,230,202	2,943,657
Equity contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 77,970	$ 61,004
Number of Contracts, Assets \| Contract	899	1,039
Fair Value, Liabilities	$ 71,604	$ 81,085
Number of Contracts, Liabilities \| Contract	1,067	1,070
Commodity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	2,498	1,726
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	1,718	1,684
Commodity contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 11,213	$ 19,342
Number of Contracts, Assets \| Contract	15	29
Fair Value, Liabilities	$ 2,124	$ 4,628
Number of Contracts, Liabilities \| Contract	14	28
Credit contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 400	$ 621
Number of Contracts, Assets \| Contract	10	39
Fair Value, Liabilities	$ 276	$ 841
Number of Contracts, Liabilities \| Contract	11	44
Credit contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 31,567	$ 16,977
Number of Contracts, Assets \| Contract	115	100
Fair Value, Liabilities	$ 52,493	$ 59,314
Number of Contracts, Liabilities \| Contract	92	135

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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- Definition

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

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