Derivative Financial Instruments - Fair Value and Related Number of Derivative Contracts Categorized by Type of Derivative Contract (Detail) $ in Thousands	Feb. 28, 2018 USD ($) Contract	Nov. 30, 2017 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net amounts per Consolidated Statements of Financial Condition, Assets	$ 149,538	$ 163,833
Net amounts per Consolidated Statements of Financial Condition, Liabilities	849,741	236,950
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	1,330,099	1,290,618
Fair Value, Liabilities	1,788,105	1,375,936
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(1,271,323)	(1,268,043)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(1,271,323)	(1,268,043)
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	471,434	1,340,384
Fair Value, Liabilities	452,566	1,275,027
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(431,247)	(1,319,895)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(445,690)	(1,274,900)
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	757,051	787,047
Fair Value, Liabilities	1,259,198	1,012,236
Amounts offset in the Consolidated Statements of Financial Condition, Assets	(706,476)	(666,278)
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities	(933,115)	(883,306)
Interest rate contracts \| Rule change by London Clearing House
Derivatives, Fair Value [Line Items]
Amounts offset in the Consolidated Statements of Financial Condition, Assets		800,000
Amounts offset in the Consolidated Statements of Financial Condition, Liabilities		800,000
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Fair Value, Assets	0	0
Fair Value, Liabilities	28,269	2,420
Designated as Hedging Instrument \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 0
Number of Contracts, Assets \| Contract	0	0
Fair Value, Liabilities	$ 28,269	$ 2,420
Number of Contracts, Liabilities \| Contract	1	1
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 2,558,584	$ 3,418,049
Fair Value, Liabilities	3,471,600	3,660,779
Not Designated as Hedging Instrument \| Interest rate contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,282	$ 1,957
Number of Contracts, Assets \| Contract	35,757	33,972
Fair Value, Liabilities	$ 0	$ 66
Number of Contracts, Liabilities \| Contract	9,024	8,515
Not Designated as Hedging Instrument \| Interest rate contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 452,564	$ 1,334,878
Number of Contracts, Assets \| Contract	2,192	2,711
Fair Value, Liabilities	$ 413,582	$ 1,263,994
Number of Contracts, Liabilities \| Contract	2,128	2,948
Not Designated as Hedging Instrument \| Interest rate contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 344,094	$ 380,223
Number of Contracts, Assets \| Contract	865	1,804
Fair Value, Liabilities	$ 535,160	$ 444,716
Number of Contracts, Liabilities \| Contract	1,503	1,346
Not Designated as Hedging Instrument \| Foreign exchange contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1	$ 157
Number of Contracts, Assets \| Contract	1,415	2,045
Fair Value, Liabilities	$ 0	$ 20
Number of Contracts, Liabilities \| Contract	189	101
Not Designated as Hedging Instrument \| Foreign exchange contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 307,003	$ 303,091
Number of Contracts, Assets \| Contract	4,274	4,338
Fair Value, Liabilities	$ 299,608	$ 286,582
Number of Contracts, Liabilities \| Contract	4,278	4,361
Not Designated as Hedging Instrument \| Equity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,326,593	$ 1,288,295
Number of Contracts, Assets \| Contract	2,397,933	2,654,555
Fair Value, Liabilities	$ 1,788,034	$ 1,375,832
Number of Contracts, Liabilities \| Contract	1,998,694	2,090,935
Not Designated as Hedging Instrument \| Equity contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 98,299	$ 78,812
Number of Contracts, Assets \| Contract	2,091	1,847
Fair Value, Liabilities	$ 410,960	$ 247,750
Number of Contracts, Liabilities \| Contract	1,983	1,722
Not Designated as Hedging Instrument \| Commodity contracts \| Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 223	$ 209
Number of Contracts, Assets \| Contract	4,066	3,723
Fair Value, Liabilities	$ 71	$ 18
Number of Contracts, Liabilities \| Contract	4,107	3,819
Not Designated as Hedging Instrument \| Credit contracts \| Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 18,870	$ 5,506
Number of Contracts, Assets \| Contract	49	18
Fair Value, Liabilities	$ 10,715	$ 8,613
Number of Contracts, Liabilities \| Contract	46	27
Not Designated as Hedging Instrument \| Credit contracts \| Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 7,655	$ 24,921
Number of Contracts, Assets \| Contract	97	110
Fair Value, Liabilities	$ 13,470	$ 33,188
Number of Contracts, Liabilities \| Contract	59	164

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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