Fair Value Disclosures - Schedule of Assets and Liabilities Measured on Recurring Basis at Fair Value (Details) - USD ($) $ in Thousands	Nov. 30, 2019	Nov. 30, 2018
Assets:
Trading assets, at fair value	$ 16,308,807	$ 17,068,897
Derivative assets	418,408	166,775
Counterparty and Cash Collateral Netting, assets	(1,433,197)	(2,413,931)
Securities purchased under agreements to resell	25,000
Securities received as collateral	9,500	0
Available for sale securities	0	1,409,886
Liabilities:
Trading liabilities, at fair value	10,532,460	9,478,946
Derivative liability	527,205	1,127,653
Counterparty and Cash Collateral Netting, liabilities	(1,632,178)	(2,513,050)
Short-term borrowings	20,981
Long-term debt	1,215,285	686,170
Obligation to Return Securities Received as Collateral	9,500	0
Level 1
Assets:
Trading assets, at fair value	5,941,623	6,091,056
Derivative assets	2,809	34,841
Securities purchased under agreements to resell	0
Securities received as collateral	9,500
Available for sale securities		1,072,856
Liabilities:
Trading liabilities, at fair value	5,971,928	4,831,081
Derivative liability	871	26,473
Short-term borrowings	0
Long-term debt	0	0
Obligation to Return Securities Received as Collateral	9,500
Level 2
Assets:
Trading assets, at fair value	11,245,763	12,688,016
Derivative assets	1,833,907	2,539,943
Securities purchased under agreements to resell	0
Securities received as collateral	0
Available for sale securities		337,030
Liabilities:
Trading liabilities, at fair value	6,086,328	7,126,481
Derivative liability	2,066,455	3,586,694
Short-term borrowings	20,981
Long-term debt	735,216	485,425
Obligation to Return Securities Received as Collateral	0
Level 3
Assets:
Trading assets, at fair value	554,618	703,756
Derivative assets	14,889	5,922
Securities purchased under agreements to resell	25,000
Securities received as collateral	0
Available for sale securities		0
Liabilities:
Trading liabilities, at fair value	106,382	34,434
Derivative liability	92,057	27,536
Short-term borrowings	0
Long-term debt	480,069	200,745
Obligation to Return Securities Received as Collateral	0
Fair Value Measured at NAV
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative investments	586,934	394,359
Corporate equity securities
Assets:
Trading assets, at fair value	2,783,993	2,667,918
Liabilities:
Trading liabilities, at fair value	2,767,526	1,686,515
Obligation to Return Securities Received as Collateral	0	0
Corporate equity securities \| Level 1
Assets:
Trading assets, at fair value	2,507,164	2,497,045
Liabilities:
Trading liabilities, at fair value	2,755,601	1,685,071
Corporate equity securities \| Level 2
Assets:
Trading assets, at fair value	218,403	118,681
Liabilities:
Trading liabilities, at fair value	7,438	1,444
Corporate equity securities \| Level 3
Assets:
Trading assets, at fair value	58,426	52,192
Liabilities:
Trading liabilities, at fair value	4,487	0
Corporate debt securities
Assets:
Trading assets, at fair value	2,479,735	2,692,664
Liabilities:
Trading liabilities, at fair value	1,471,482	1,506,140
Obligation to Return Securities Received as Collateral	0	0
Corporate debt securities \| Level 1
Assets:
Trading assets, at fair value	0	0
Liabilities:
Trading liabilities, at fair value	0	0
Corporate debt securities \| Level 2
Assets:
Trading assets, at fair value	2,472,245	2,683,180
Liabilities:
Trading liabilities, at fair value	1,471,142	1,505,618
Corporate debt securities \| Level 3
Assets:
Trading assets, at fair value	7,490	9,484
Liabilities:
Trading liabilities, at fair value	340	522
Collateralized debt obligations and collateralized loan obligations
Assets:
Trading assets, at fair value	153,013	109,054
Collateralized debt obligations and collateralized loan obligations \| Level 1
Assets:
Trading assets, at fair value	0	0
Collateralized debt obligations and collateralized loan obligations \| Level 2
Assets:
Trading assets, at fair value	124,225	72,949
Collateralized debt obligations and collateralized loan obligations \| Level 3
Assets:
Trading assets, at fair value	28,788	36,105
U.S. government and federal agency securities
Assets:
Trading assets, at fair value	2,260,242	1,846,206
Available for sale securities		1,072,856
Liabilities:
Trading liabilities, at fair value	1,851,981	1,384,295
U.S. government and federal agency securities \| Level 1
Assets:
Trading assets, at fair value	2,101,624	1,789,614
Liabilities:
Trading liabilities, at fair value	1,851,981	1,384,295
U.S. government and federal agency securities \| Level 2
Assets:
Trading assets, at fair value	158,618	56,592
Liabilities:
Trading liabilities, at fair value	0	0
U.S. government and federal agency securities \| Level 3
Assets:
Trading assets, at fair value	0	0
Liabilities:
Trading liabilities, at fair value	0	0
Municipal securities
Assets:
Trading assets, at fair value	742,326	894,253
Liabilities:
Obligation to Return Securities Received as Collateral	0	0
Municipal securities \| Level 1
Assets:
Trading assets, at fair value	0	0
Municipal securities \| Level 2
Assets:
Trading assets, at fair value	742,326	894,253
Municipal securities \| Level 3
Assets:
Trading assets, at fair value	0	0
Sovereign obligations
Assets:
Trading assets, at fair value	2,735,853	2,812,965
Liabilities:
Trading liabilities, at fair value	2,304,540	2,396,337
Obligation to Return Securities Received as Collateral	0	0
Sovereign obligations \| Level 1
Assets:
Trading assets, at fair value	1,330,026	1,769,556
Liabilities:
Trading liabilities, at fair value	1,363,475	1,735,242
Sovereign obligations \| Level 2
Assets:
Trading assets, at fair value	1,405,827	1,043,409
Liabilities:
Trading liabilities, at fair value	941,065	661,095
Sovereign obligations \| Level 3
Assets:
Trading assets, at fair value	0	0
Liabilities:
Trading liabilities, at fair value	0	0
Residential mortgage-backed securities
Assets:
Trading assets, at fair value	1,086,806	2,183,232
Available for sale securities		210,518
Residential mortgage-backed securities \| Level 1
Assets:
Trading assets, at fair value	0	0
Available for sale securities		0
Residential mortgage-backed securities \| Level 2
Assets:
Trading assets, at fair value	1,069,066	2,163,629
Available for sale securities		210,518
Residential mortgage-backed securities \| Level 3
Assets:
Trading assets, at fair value	17,740	19,603
Available for sale securities		0
Commercial mortgage-backed securities
Assets:
Trading assets, at fair value	430,170	830,292
Available for sale securities		15,642
Liabilities:
Trading liabilities, at fair value	35
Commercial mortgage-backed securities \| Level 1
Assets:
Trading assets, at fair value	0	0
Available for sale securities		0
Liabilities:
Trading liabilities, at fair value	0
Commercial mortgage-backed securities \| Level 2
Assets:
Trading assets, at fair value	424,060	819,406
Available for sale securities		15,642
Liabilities:
Trading liabilities, at fair value	0
Commercial mortgage-backed securities \| Level 3
Assets:
Trading assets, at fair value	6,110	10,886
Available for sale securities		0
Liabilities:
Trading liabilities, at fair value	35
Other asset-backed securities
Assets:
Trading assets, at fair value	346,410	292,556
Available for sale securities		110,870
Other asset-backed securities \| Level 1
Assets:
Trading assets, at fair value	0	0
Available for sale securities		0
Other asset-backed securities \| Level 2
Assets:
Trading assets, at fair value	303,847	239,381
Available for sale securities		110,870
Other asset-backed securities \| Level 3
Assets:
Trading assets, at fair value	42,563	53,175
Available for sale securities		0
Loans and other receivables
Assets:
Trading assets, at fair value	2,574,631	2,103,578
Liabilities:
Obligation to Return Securities Received as Collateral	0	0
Loans and other receivables \| Level 1
Assets:
Trading assets, at fair value	0	0
Loans and other receivables \| Level 2
Assets:
Trading assets, at fair value	2,460,551	2,056,593
Loans and other receivables \| Level 3
Assets:
Trading assets, at fair value	114,080	46,985
Investments at fair value
Assets:
Trading assets, at fair value	238,100	396,254
Investments at fair value \| Level 1
Assets:
Trading assets, at fair value	0	0
Investments at fair value \| Level 2
Assets:
Trading assets, at fair value	32,688	0
Investments at fair value \| Level 3
Assets:
Trading assets, at fair value	205,412	396,254
FXCM term loan
Assets:
Trading assets, at fair value	59,120	73,150
FXCM term loan \| Level 1
Assets:
Trading assets, at fair value	0	0
FXCM term loan \| Level 2
Assets:
Trading assets, at fair value	0	0
FXCM term loan \| Level 3
Assets:
Trading assets, at fair value	59,120	73,150
Loans
Liabilities:
Trading liabilities, at fair value	1,609,691	1,378,006
Loans \| Level 1
Liabilities:
Trading liabilities, at fair value	0	0
Loans \| Level 2
Liabilities:
Trading liabilities, at fair value	1,600,228	1,371,630
Loans \| Level 3
Liabilities:
Trading liabilities, at fair value	$ 9,463	6,376
U.S. government securities
Assets:
Available for sale securities		1,072,856
U.S. government securities \| Level 1
Assets:
Available for sale securities		1,072,856
U.S. government securities \| Level 2
Assets:
Available for sale securities		0
U.S. government securities \| Level 3
Assets:
Available for sale securities		$ 0

Financial Instruments Owned Trading Assets, at Fair Value, Excluding Investments Based on Net Asset Value

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Fair value of liability associated with 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.

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Fair value portion of federal funds sold and securities borrowed or purchased under agreements to resell.

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