Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Detail) $ in Thousands	May 31, 2017 USD ($) Contract	Nov. 30, 2016 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 178,431	$ 360,534
Net amounts per Consolidated Statements of Financial Condition, Liabilities	440,404	637,535
Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	415,900	715,042
Fair Value, Liabilities	720,420	1,095,606
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(409,282)	(691,009)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(409,282)	(691,009)
Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,852,803	2,836,457
Fair Value, Liabilities	1,803,102	2,638,773
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,841,960)	(2,751,650)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,789,139)	(2,638,774)
Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	781,926	1,065,034
Fair Value, Liabilities	776,562	1,132,370
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(620,956)	(813,340)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(661,259)	(899,431)
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	10,448
Fair Value, Liabilities	0
Designated as Hedging Instrument [Member] \| Interest rate contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 10,448
Number of Contracts, Assets \| Contract	1
Fair Value, Liabilities	$ 0
Number of Contracts, Liabilities \| Contract	0
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,040,181
Fair Value, Liabilities	3,300,084
Not Designated as Hedging Instrument [Member] \| Interest rate contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 632	$ 2,275
Number of Contracts, Assets \| Contract	17,359	24,300
Fair Value, Liabilities	$ 73	$ 24
Number of Contracts, Liabilities \| Contract	48,603	29,773
Not Designated as Hedging Instrument [Member] \| Interest rate contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,815,375	$ 2,835,812
Number of Contracts, Assets \| Contract	3,485	3,596
Fair Value, Liabilities	$ 1,765,864	$ 2,636,469
Number of Contracts, Liabilities \| Contract	3,750	3,445
Not Designated as Hedging Instrument [Member] \| Interest rate contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 417,755	$ 444,159
Number of Contracts, Assets \| Contract	1,691	1,136
Fair Value, Liabilities	$ 386,018	$ 522,965
Number of Contracts, Liabilities \| Contract	559	1,627
Not Designated as Hedging Instrument [Member] \| Foreign exchange contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	496	376
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	176	686
Not Designated as Hedging Instrument [Member] \| Foreign exchange contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 295,104	$ 529,609
Number of Contracts, Assets \| Contract	5,416	7,448
Fair Value, Liabilities	$ 293,527	$ 516,869
Number of Contracts, Liabilities \| Contract	5,688	7,633
Not Designated as Hedging Instrument [Member] \| Equity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 415,268	$ 712,767
Number of Contracts, Assets \| Contract	1,975,152	2,820,702
Fair Value, Liabilities	$ 720,347	$ 1,095,582
Number of Contracts, Liabilities \| Contract	1,696,985	2,410,956
Not Designated as Hedging Instrument [Member] \| Equity contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 51,826	$ 72,041
Number of Contracts, Assets \| Contract	1,161	1,077
Fair Value, Liabilities	$ 79,257	$ 67,033
Number of Contracts, Liabilities \| Contract	1,134	1,191
Not Designated as Hedging Instrument [Member] \| Commodity contracts [Member] \| Exchange-traded [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	5,020	1,356
Fair Value, Liabilities	$ 0	$ 0
Number of Contracts, Liabilities \| Contract	5,155	920
Not Designated as Hedging Instrument [Member] \| Credit contracts [Member] \| Cleared OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 26,980	$ 645
Number of Contracts, Assets \| Contract	59	6
Fair Value, Liabilities	$ 37,238	$ 2,304
Number of Contracts, Liabilities \| Contract	72	8
Not Designated as Hedging Instrument [Member] \| Credit contracts [Member] \| Bilateral OTC [Member]
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 17,241	$ 19,225
Number of Contracts, Assets \| Contract	148	213
Fair Value, Liabilities	$ 17,760	$ 25,503
Number of Contracts, Liabilities \| Contract	142	184
Rule Change by Chicago Mercantile Exchange [Member] \| Interest rate contracts [Member]
Derivatives, Fair Value [Line Items]
Amounts offset in the Consolidated Statements of Financial Condition, Assets		$ 1,000,000
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities		$ 1,000,000

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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