Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Feb. 28, 2018	Nov. 30, 2017
Financial instruments owned:
Corporate equity securities	$ 2,227,964	$ 1,880,553
Corporate debt securities	2,891,650	3,287,336
Collateralized debt obligations and collateralized loan obligations	170,938	169,170
U.S. government and federal agency securities	887,155	1,308,673
Municipal securities	713,643	710,513
Sovereign obligations	2,452,120	2,417,459
Loans and other receivables	2,180,614	1,667,885
Derivatives	149,538	163,833
Investments at fair value	79,879	94,400
Total financial instruments owned, excluding Investments at fair value based on NAV	14,990,746	13,977,967
Counterparty and Cash Collateral Netting	(2,409,046)	(3,254,216)
Securities received as collateral	0	103
Financial instruments sold, not yet purchased:
Corporate equity securities	1,774,765	1,488,845
Corporate debt securities	1,596,297	1,689,347
U.S. government and federal agency securities	1,398,020	1,430,737
Municipal securities	7,659
Sovereign obligations	2,132,295	2,173,635
Loans	1,871,601	1,152,310
Derivatives	849,741	236,950
Total financial instruments sold, not yet purchased	9,630,413	8,171,929
Counterparty and Cash Collateral Netting	(2,650,128)	(3,426,249)
Short-term borrowings	0	23,324
Long-term debt	735,456	606,956
Obligation to return securities received as collateral	0	103
Level 1 to Level 2 transfers, amount	20,800
Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	2,378,843	1,479,371
Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	520,655	520,534
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	35	105
Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	337,747	278,240
Level 1
Financial instruments owned:
Corporate equity securities	2,127,451	1,801,453
Corporate debt securities	0	0
Collateralized debt obligations and collateralized loan obligations	0	0
U.S. government and federal agency securities	844,212	1,269,230
Municipal securities	0	0
Sovereign obligations	1,312,317	1,381,552
Loans and other receivables	0	0
Derivatives	8,651	160,168
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	4,292,631	4,612,403
Securities received as collateral		103
Financial instruments sold, not yet purchased:
Corporate equity securities	1,768,112	1,456,675
Corporate debt securities	0	0
U.S. government and federal agency securities	1,398,020	1,430,737
Municipal securities	0
Sovereign obligations	1,208,396	1,216,643
Loans	0	0
Derivatives	11,451	247,919
Total financial instruments sold, not yet purchased	4,385,979	4,351,974
Short-term borrowings		0
Long-term debt	0	0
Obligation to return securities received as collateral		103
Level 1 \| Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 1 \| Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	0	0
Level 1 \| Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 2
Financial instruments owned:
Corporate equity securities	65,101	57,091
Corporate debt securities	2,865,547	3,261,300
Collateralized debt obligations and collateralized loan obligations	144,505	139,166
U.S. government and federal agency securities	42,943	39,443
Municipal securities	713,643	710,513
Sovereign obligations	1,139,803	1,035,907
Loans and other receivables	2,118,571	1,620,581
Derivatives	2,545,221	3,248,586
Investments at fair value	0	946
Total financial instruments owned, excluding Investments at fair value based on NAV	12,784,426	12,292,053
Securities received as collateral		0
Financial instruments sold, not yet purchased:
Corporate equity securities	6,592	32,122
Corporate debt securities	1,595,775	1,688,825
U.S. government and federal agency securities	0	0
Municipal securities	7,659
Sovereign obligations	923,899	956,992
Loans	1,861,278	1,148,824
Derivatives	3,476,824	3,399,239
Total financial instruments sold, not yet purchased	7,872,027	7,226,002
Short-term borrowings		23,324
Long-term debt	735,456	606,956
Obligation to return securities received as collateral		0
Level 2 \| Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	2,357,081	1,453,294
Level 2 \| Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	505,552	508,115
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	0	0
Level 2 \| Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	286,459	217,111
Level 3
Financial instruments owned:
Corporate equity securities	35,412	22,009
Corporate debt securities	26,103	26,036
Collateralized debt obligations and collateralized loan obligations	26,433	30,004
U.S. government and federal agency securities	0	0
Municipal securities	0	0
Sovereign obligations	0	0
Loans and other receivables	62,043	47,304
Derivatives	4,712	9,295
Investments at fair value	79,879	93,454
Total financial instruments owned, excluding Investments at fair value based on NAV	322,735	327,727
Securities received as collateral		0
Financial instruments sold, not yet purchased:
Corporate equity securities	61	48
Corporate debt securities	522	522
U.S. government and federal agency securities	0	0
Municipal securities	0
Sovereign obligations	0	0
Loans	10,323	3,486
Derivatives	11,594	16,041
Total financial instruments sold, not yet purchased	22,535	20,202
Short-term borrowings		0
Long-term debt	0	0
Obligation to return securities received as collateral		0
Level 3 \| Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	21,762	26,077
Level 3 \| Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	15,103	12,419
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	35	105
Level 3 \| Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	$ 51,288	$ 61,129

Fair value of loan obligations.

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The fair value as of the balance sheet date of firm holdings in structured asset - backed securities whose value and payments are derived from portfolio of fixed income underlying assets.

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The fair value as of the balance sheet date of firm holdings in corporate loans, participation certificates in GNMA project and construction loans, and escrow and trade claim receivables.

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Financial Instruments, Owned, at Fair Value Excluding Investments at Net Asset Value

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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, and obligation to return cash collateral under master netting arrangements.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Fair value of firm holdings in corporate fixed income securities. Includes pledged and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in corporate stocks (common and preferred), stock options, warrants and any other financial instrument which represents, or provides the ability to obtain, ownership rights in a corporation. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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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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The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in fixed income obligations issued by foreign governments. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in private equity, mezzanine, venture capital, merchant banking, real estate and special situations investments. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in fixed income obligations issued by state and local governments and authorities. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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Fair value of obligations incurred from short sales.

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Fair value of obligations arising from corporate debt obligations sold short.

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Fair value of obligations arising from corporate equity sold short.

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

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Fair value of obligations arising from mortgages, mortgage-backed securities and asset-backed securities sold short.

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Fair value of obligations arising from foreign government debt obligations short.

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Fair value of obligations arising from state and municipal debt obligations sold short.

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Fair value of obligations arising from US treasury and other US government and agency debt obligations sold short.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The fair value of collateral received by the entity associated with securities borrowed that must be returned if the counterparty fulfills its obligations. It appears on the balance sheet as a liability and has a corresponding asset that appears on the balance sheet called Securities Received as Collateral.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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