Derivative Financial Instruments (Fair Value And Related Number Of Derivative Contracts Categorized By Predominant Risk Exposure) (Details) $ in Thousands	May 31, 2019 USD ($) Contract	Nov. 30, 2018 USD ($) Contract
Derivatives, Fair Value [Line Items]
Net Amounts in Consolidated Statements of Financial Condition	$ 356,499	$ 166,775
Net Amounts in Consolidated Statements of Financial Condition	554,243	1,127,653
Designated as Accounting Hedges \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	13,348	0
Fair Value, Liabilities	0	29,647
Not Designated as Accounting Hedges
Derivatives, Fair Value [Line Items]
Fair Value, Assets	2,540,914	2,580,706
Fair Value, Liabilities	2,924,251	3,611,056
Exchange-traded
Derivatives, Fair Value [Line Items]
Fair Value, Assets	628,487	1,231,525
Fair Value, Liabilities	923,508	2,061,924
Amounts offset in Consolidated Statement of Financial Condition, Assets	(603,556)	(1,190,951)
Amounts offset in Consolidated Statement of Financial Condition, Liabilities	(603,556)	(1,190,951)
Exchange-traded \| Not Designated as Accounting Hedges \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,070	$ 924
Number of Contracts, Assets \| Contract	41,702	32,159
Fair Value, Liabilities	$ 1,835	$ 513
Number of Contracts, Liabilities \| Contract	64,221	66,095
Exchange-traded \| Not Designated as Accounting Hedges \| Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 0	$ 42
Number of Contracts, Assets \| Contract	36	538
Fair Value, Liabilities	$ 0	$ 2
Number of Contracts, Liabilities \| Contract	59	690
Exchange-traded \| Not Designated as Accounting Hedges \| Equity contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 621,087	$ 1,202,927
Number of Contracts, Assets \| Contract	1,703,475	2,104,684
Fair Value, Liabilities	$ 921,170	$ 2,061,137
Number of Contracts, Liabilities \| Contract	1,327,055	1,779,836
Exchange-traded \| Not Designated as Accounting Hedges \| Commodity contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 6,330	$ 27,632
Number of Contracts, Assets \| Contract	6,492	7,272
Fair Value, Liabilities	$ 503	$ 272
Number of Contracts, Liabilities \| Contract	6,904	4,185
Cleared OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 914,140	$ 433,874
Fair Value, Liabilities	957,460	443,072
Amounts offset in Consolidated Statement of Financial Condition, Assets	(897,715)	(407,351)
Amounts offset in Consolidated Statement of Financial Condition, Liabilities	(902,183)	(418,779)
Cleared OTC \| Designated as Accounting Hedges \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 13,348	$ 0
Number of Contracts, Assets \| Contract	1	0
Fair Value, Liabilities	$ 0	$ 29,647
Number of Contracts, Liabilities \| Contract	0	1
Cleared OTC \| Not Designated as Accounting Hedges \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 897,615	$ 422,670
Number of Contracts, Assets \| Contract	2,907	2,095
Fair Value, Liabilities	$ 952,865	$ 411,833
Number of Contracts, Liabilities \| Contract	3,360	2,394
Cleared OTC \| Not Designated as Accounting Hedges \| Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets		$ 0
Number of Contracts, Assets \| Contract		0
Fair Value, Liabilities		$ 36
Number of Contracts, Liabilities \| Contract		3
Cleared OTC \| Not Designated as Accounting Hedges \| Credit contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 3,177	$ 11,204
Number of Contracts, Assets \| Contract	24	7
Fair Value, Liabilities	$ 4,595	$ 1,556
Number of Contracts, Liabilities \| Contract	24	14
Bilateral OTC
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 1,011,635	$ 915,307
Fair Value, Liabilities	1,043,283	1,135,707
Amounts offset in Consolidated Statement of Financial Condition, Assets	(696,492)	(815,629)
Amounts offset in Consolidated Statement of Financial Condition, Liabilities	(864,269)	(903,320)
Bilateral OTC \| Not Designated as Accounting Hedges \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 405,268	$ 372,899
Number of Contracts, Assets \| Contract	2,002	1,398
Fair Value, Liabilities	$ 239,880	$ 491,697
Number of Contracts, Liabilities \| Contract	752	816
Bilateral OTC \| Not Designated as Accounting Hedges \| Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 400,432	$ 311,228
Number of Contracts, Assets \| Contract	12,320	9,548
Fair Value, Liabilities	$ 412,485	$ 314,951
Number of Contracts, Liabilities \| Contract	12,544	9,909
Bilateral OTC \| Not Designated as Accounting Hedges \| Equity contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 166,068	$ 207,221
Number of Contracts, Assets \| Contract	3,195	5,126
Fair Value, Liabilities	$ 374,665	$ 315,996
Number of Contracts, Liabilities \| Contract	3,835	2,764
Bilateral OTC \| Not Designated as Accounting Hedges \| Commodity contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 30,792	$ 10,191
Number of Contracts, Assets \| Contract	2,283	1,274
Fair Value, Liabilities	$ 4,355	$ 1,445
Number of Contracts, Liabilities \| Contract	1,787	1,498
Bilateral OTC \| Not Designated as Accounting Hedges \| Credit contracts
Derivatives, Fair Value [Line Items]
Fair Value, Assets	$ 9,075	$ 13,768
Number of Contracts, Assets \| Contract	98	123
Fair Value, Liabilities	$ 11,898	$ 11,618
Number of Contracts, Liabilities \| Contract	58	79

Derivative, Fair Value of Derivative Asset, Amount Netting in Consolidated Statement of Financial Condition

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Derivative, Fair Value of Derivative Liability, Amount Netting in Consolidated Statement of Financial Condition

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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, after the 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 not subject to a master netting arrangement and not elected to be offset.

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