Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	May 31, 2017	Nov. 30, 2016
Financial instruments owned:
Corporate equity securities	$ 2,166,832	$ 1,854,864
Corporate debt securities	2,947,499	2,700,025
Collateralized debt obligations and collateralized loan obligations	50,774	108,660
U.S. government and federal agency securities	1,621,823	2,446,123
Municipal securities	600,039	735,726
Sovereign obligations	2,382,584	2,423,048
Loans and other receivables	1,732,795	1,639,105
Derivatives	178,431	360,534
Investments at fair value	89,006	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	13,857,562	13,785,203
Counterparty and Cash Collateral Netting	(2,872,198)	(4,255,998)
Financial instruments sold, not yet purchased:
Corporate equity securities	1,428,414	1,594,524
Corporate debt securities	1,786,687	1,718,947
U.S. government and federal agency securities	1,354,488	976,497
Sovereign obligations	2,696,733	2,629,344
Loans	1,296,661	802,355
Derivatives	440,404	637,535
Total financial instruments sold, not yet purchased	9,004,535	8,359,202
Counterparty and Cash Collateral Netting	(2,859,680)	(4,229,213)
Other secured financings		41,768
Short-term borrowings	28,044
Long-term debt	392,807	248,856
RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,452,301	999,266
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	1,078
CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	450,221	316,985
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	70
Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	185,257	104,498
Level 1 [Member]
Financial instruments owned:
Corporate equity securities	1,956,279	1,742,463
Corporate debt securities	0	0
Collateralized debt obligations and collateralized loan obligations	0	0
U.S. government and federal agency securities	1,531,038	2,389,397
Municipal securities	0	0
Sovereign obligations	1,326,731	1,432,556
Loans and other receivables	1,677	0
Derivatives	45,866	3,825
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	4,861,591	5,568,241
Financial instruments sold, not yet purchased:
Corporate equity securities	1,398,522	1,577,405
Corporate debt securities	0	0
U.S. government and federal agency securities	1,354,488	976,497
Sovereign obligations	1,502,643	1,375,590
Loans	0	0
Derivatives	42,617	568
Total financial instruments sold, not yet purchased	4,298,270	3,930,060
Other secured financings		0
Short-term borrowings	0
Long-term debt	0	0
Level 1 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	0
Level 1 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	0
Level 1 [Member] \| Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 2 [Member]
Financial instruments owned:
Corporate equity securities	190,005	90,662
Corporate debt securities	2,922,772	2,675,020
Collateralized debt obligations and collateralized loan obligations	23,519	54,306
U.S. government and federal agency securities	90,785	56,726
Municipal securities	600,039	708,469
Sovereign obligations	1,055,853	990,492
Loans and other receivables	1,681,753	1,557,233
Derivatives	2,997,903	4,606,278
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	11,557,764	12,059,672
Financial instruments sold, not yet purchased:
Corporate equity securities	29,538	16,806
Corporate debt securities	1,786,165	1,718,424
U.S. government and federal agency securities	0	0
Sovereign obligations	1,194,090	1,253,754
Loans	1,291,694	801,977
Derivatives	3,247,585	4,856,310
Total financial instruments sold, not yet purchased	7,550,150	8,647,271
Other secured financings		41,350
Short-term borrowings	28,044
Long-term debt	392,807	248,856
Level 2 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,419,269	960,494
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	1,078
Level 2 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	433,958	296,405
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	0
Level 2 [Member] \| Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	141,908	63,587
Level 3 [Member]
Financial instruments owned:
Corporate equity securities	20,548	21,739
Corporate debt securities	24,727	25,005
Collateralized debt obligations and collateralized loan obligations	27,255	54,354
U.S. government and federal agency securities	0	0
Municipal securities	0	27,257
Sovereign obligations	0	0
Loans and other receivables	49,365	81,872
Derivatives	6,860	6,429
Investments at fair value	89,006	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	310,405	413,288
Financial instruments sold, not yet purchased:
Corporate equity securities	354	313
Corporate debt securities	522	523
U.S. government and federal agency securities	0	0
Sovereign obligations	0	0
Loans	4,967	378
Derivatives	9,882	9,870
Total financial instruments sold, not yet purchased	15,795	11,084
Other secured financings		418
Short-term borrowings	0
Long-term debt	0	0
Level 3 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	33,032	38,772
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	0
Level 3 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	16,263	20,580
Financial instruments sold, not yet purchased:
Financial Instruments Sold, Not yet Purchased, Mortgages, Mortgage-backed and Asset-backed Securities	70
Level 3 [Member] \| Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	$ 43,349	$ 40,911

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 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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-Publisher FASB
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This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents the amount of short-term debt existing as of the balance sheet date.

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