Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Nov. 30, 2016	Nov. 30, 2015
Financial instruments owned:
Corporate equity securities	$ 1,854,864	$ 2,027,989
Corporate debt securities	2,700,025	2,893,041
CDOs and CLOs	108,660	174,236
U.S. government and federal agency securities	2,446,123	2,645,651
Municipal securities	735,726	487,141
Sovereign obligations	2,423,048	2,659,441
Loans and other receivables	1,639,105	1,312,333
Derivatives	360,534	251,080
Investments at fair value	96,369	79,344
Total financial instruments owned, excluding Investments at fair value based on NAV	13,785,203	16,522,382
Counterparty and Cash Collateral Netting	(4,255,998)	(4,165,446)
Financial instruments sold, not yet purchased:
Corporate equity securities	1,594,524	1,418,933
Corporate debt securities	1,718,947	1,556,941
U.S. government and federal agency securities	976,497	1,488,121
Sovereign obligations	2,629,344	1,342,996
Loans	802,355	769,408
Derivatives	637,535	208,548
Total financial instruments sold, not yet purchased	8,359,202	6,785,064
Counterparty and Cash Collateral Netting	(4,229,213)	(4,257,998)
Other secured financings	41,768	68,345
Long term debt	248,856	0
Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	999,266	2,801,333
Financial instruments sold, not yet purchased:
Residential mortgage-backed securities		117
Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	316,985	1,029,239
Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	104,498	161,554
Level 1 [Member]
Financial instruments owned:
Corporate equity securities	1,742,463	1,853,351
Corporate debt securities	0	0
CDOs and CLOs	0	0
U.S. government and federal agency securities	2,389,397	2,555,018
Municipal securities	0	0
Sovereign obligations	1,432,556	1,251,366
Loans and other receivables	0	0
Derivatives	3,825	1,037
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	5,568,241	5,660,772
Financial instruments sold, not yet purchased:
Corporate equity securities	1,577,405	1,382,377
Corporate debt securities	0	0
U.S. government and federal agency securities	976,497	1,488,121
Sovereign obligations	1,375,590	837,614
Loans	0	0
Derivatives	568	364
Total financial instruments sold, not yet purchased	3,930,060	3,708,476
Other secured financings	0	0
Long term debt	0
Level 1 [Member] \| Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Financial instruments sold, not yet purchased:
Residential mortgage-backed securities		0
Level 1 [Member] \| Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 1 [Member] \| Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 2 [Member]
Financial instruments owned:
Corporate equity securities	90,662	133,732
Corporate debt securities	2,675,020	2,867,165
CDOs and CLOs	54,306	89,144
U.S. government and federal agency securities	56,726	90,633
Municipal securities	708,469	487,141
Sovereign obligations	990,492	1,407,955
Loans and other receivables	1,557,233	1,123,044
Derivatives	4,606,278	4,395,704
Investments at fair value	0	26,224
Total financial instruments owned, excluding Investments at fair value based on NAV	12,059,672	14,485,354
Financial instruments sold, not yet purchased:
Corporate equity securities	16,806	36,518
Corporate debt securities	1,718,424	1,556,941
U.S. government and federal agency securities	0	0
Sovereign obligations	1,253,754	505,382
Loans	801,977	758,939
Derivatives	4,856,310	4,446,639
Total financial instruments sold, not yet purchased	8,647,271	7,304,536
Other secured financings	41,350	67,801
Long term debt	248,856
Level 2 [Member] \| Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	960,494	2,731,070
Financial instruments sold, not yet purchased:
Residential mortgage-backed securities		117
Level 2 [Member] \| Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	296,405	1,014,913
Level 2 [Member] \| Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	63,587	118,629
Level 3 [Member]
Financial instruments owned:
Corporate equity securities	21,739	40,906
Corporate debt securities	25,005	25,876
CDOs and CLOs	54,354	85,092
U.S. government and federal agency securities	0	0
Municipal securities	27,257	0
Sovereign obligations	0	120
Loans and other receivables	81,872	189,289
Derivatives	6,429	19,785
Investments at fair value	96,369	53,120
Total financial instruments owned, excluding Investments at fair value based on NAV	413,288	541,702
Financial instruments sold, not yet purchased:
Corporate equity securities	313	38
Corporate debt securities	523	0
U.S. government and federal agency securities	0	0
Sovereign obligations	0	0
Loans	378	10,469
Derivatives	9,870	19,543
Total financial instruments sold, not yet purchased	11,084	30,050
Other secured financings	418	544
Long term debt	0
Level 3 [Member] \| Residential mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	38,772	70,263
Financial instruments sold, not yet purchased:
Residential mortgage-backed securities		0
Level 3 [Member] \| Commercial mortgage-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	20,580	14,326
Level 3 [Member] \| Other asset-backed securities [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	$ 40,911	$ 42,925

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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Fair value of asset associated with 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, and right to receive cash collateral under master netting arrangements.

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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 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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Amount of collateralized debt obligations classified as other.

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