Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Feb. 28, 2017	Nov. 30, 2016
Financial instruments owned:
Corporate equity securities	$ 1,744,545	$ 1,854,864
Corporate debt securities	2,455,947	2,700,025
CDOs and CLOs	85,253	108,660
U.S. government and federal agency securities	1,153,045	2,446,123
Municipal securities	740,658	735,726
Sovereign obligations	2,819,227	2,423,048
Loans and other receivables	1,782,399	1,639,105
Derivatives	186,502	360,534
Investments at fair value	83,785	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	13,228,565	13,785,203
Counterparty and Cash Collateral Netting	(2,826,763)	(4,255,998)
Financial instruments sold, not yet purchased:
Corporate equity securities	1,488,723	1,594,524
Corporate debt securities	1,545,468	1,718,947
U.S. government and federal agency securities	841,725	976,497
Sovereign obligations	2,986,470	2,629,344
Loans	1,492,524	802,355
Derivatives	373,581	637,535
Total financial instruments sold, not yet purchased	8,728,491	8,359,202
Counterparty and Cash Collateral Netting	(2,794,432)	(4,229,213)
Other secured financings	34,187	41,768
Long-term debt	310,057	248,856
RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,439,474	999,266
CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	586,147	316,985
Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	151,583	104,498
Level 1 [Member]
Financial instruments owned:
Corporate equity securities	1,637,621	1,742,463
Corporate debt securities	0	0
CDOs and CLOs	0	0
U.S. government and federal agency securities	1,124,343	2,389,397
Municipal securities	0	0
Sovereign obligations	1,506,428	1,432,556
Loans and other receivables	0	0
Derivatives	4,470	3,825
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	4,272,862	5,568,241
Financial instruments sold, not yet purchased:
Corporate equity securities	1,455,823	1,577,405
Corporate debt securities	0	0
U.S. government and federal agency securities	841,725	976,497
Sovereign obligations	1,500,854	1,375,590
Loans	0	0
Derivatives	4,110	568
Total financial instruments sold, not yet purchased	3,802,512	3,930,060
Other secured financings	0	0
Long-term debt	0	0
Level 1 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	0
Level 1 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	0	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	86,344	90,662
Corporate debt securities	2,422,480	2,675,020
CDOs and CLOs	39,899	54,306
U.S. government and federal agency securities	28,702	56,726
Municipal securities	714,104	708,469
Sovereign obligations	1,312,799	990,492
Loans and other receivables	1,729,227	1,557,233
Derivatives	3,003,890	4,606,278
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	11,417,035	12,059,672
Financial instruments sold, not yet purchased:
Corporate equity securities	32,576	16,806
Corporate debt securities	1,544,945	1,718,424
U.S. government and federal agency securities	0	0
Sovereign obligations	1,485,616	1,253,754
Loans	1,491,488	801,977
Derivatives	3,152,585	4,856,310
Total financial instruments sold, not yet purchased	7,707,210	8,647,271
Other secured financings	34,100	41,350
Long-term debt	310,057	248,856
Level 2 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,400,215	960,494
Level 2 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	565,494	296,405
Level 2 [Member] \| Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	113,881	63,587
Level 3 [Member]
Financial instruments owned:
Corporate equity securities	20,580	21,739
Corporate debt securities	33,467	25,005
CDOs and CLOs	45,354	54,354
U.S. government and federal agency securities	0	0
Municipal securities	26,554	27,257
Sovereign obligations	0	0
Loans and other receivables	53,172	81,872
Derivatives	4,905	6,429
Investments at fair value	83,785	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	365,431	413,288
Financial instruments sold, not yet purchased:
Corporate equity securities	324	313
Corporate debt securities	523	523
U.S. government and federal agency securities	0	0
Sovereign obligations	0	0
Loans	1,036	378
Derivatives	11,318	9,870
Total financial instruments sold, not yet purchased	13,201	11,084
Other secured financings	87	418
Long-term debt	0	0
Level 3 [Member] \| RMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	39,259	38,772
Level 3 [Member] \| CMBS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	20,653	20,580
Level 3 [Member] \| Other ABS [Member]
Financial instruments owned:
Mortgage- and asset-backed securities, assets	$ 37,702	$ 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 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 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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