Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Nov. 30, 2017	Nov. 30, 2016
Financial instruments owned:
Corporate equity securities	$ 1,880,553	$ 1,854,864
Corporate debt securities	3,287,336	2,700,025
CDOs and CLOs	169,170	108,660
U.S. government and federal agency securities	1,308,673	2,446,123
Municipal securities	710,513	735,726
Sovereign obligations	2,417,459	2,423,048
Loans and other receivables	1,667,885	1,639,105
Derivatives	163,833	360,534
Investments at fair value	94,400	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	13,977,967	13,785,203
Counterparty and Cash Collateral Netting	(3,254,216)	(4,255,998)
Securities received as collateral	103	0
Financial instruments sold, not yet purchased:
Corporate equity securities	1,488,845	1,594,524
Corporate debt securities	1,689,347	1,718,947
U.S. government and federal agency securities	1,430,737	976,497
Sovereign obligations	2,173,635	2,629,344
Loans	1,152,310	802,355
Derivatives	236,950	637,535
Total financial instruments sold, not yet purchased	8,171,929	8,359,202
Counterparty and Cash Collateral Netting	(3,426,249)	(4,229,213)
Other secured financings		41,768
Short-term borrowings	23,324	0
Long-term debt	606,956	248,856
Obligation to return securities received as collateral	103	0
Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,479,371	999,266
Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	520,534	316,985
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	105
Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	278,240	104,498
Level 1
Financial instruments owned:
Corporate equity securities	1,801,453	1,742,463
Corporate debt securities	0	0
CDOs and CLOs	0	0
U.S. government and federal agency securities	1,269,230	2,389,397
Municipal securities	0	0
Sovereign obligations	1,381,552	1,432,556
Loans and other receivables	0	0
Derivatives	160,168	3,825
Investments at fair value	0	0
Total financial instruments owned, excluding Investments at fair value based on NAV	4,612,403	5,568,241
Securities received as collateral	103
Financial instruments sold, not yet purchased:
Corporate equity securities	1,456,675	1,577,405
Corporate debt securities	0	0
U.S. government and federal agency securities	1,430,737	976,497
Sovereign obligations	1,216,643	1,375,590
Loans	0	0
Derivatives	247,919	568
Total financial instruments sold, not yet purchased	4,351,974	3,930,060
Other secured financings		0
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
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	57,091	90,662
Corporate debt securities	3,261,300	2,675,020
CDOs and CLOs	139,166	54,306
U.S. government and federal agency securities	39,443	56,726
Municipal securities	710,513	708,469
Sovereign obligations	1,035,907	990,492
Loans and other receivables	1,620,581	1,557,233
Derivatives	3,248,586	4,606,278
Investments at fair value	946	0
Total financial instruments owned, excluding Investments at fair value based on NAV	12,292,053	12,059,672
Securities received as collateral	0
Financial instruments sold, not yet purchased:
Corporate equity securities	32,122	16,806
Corporate debt securities	1,688,825	1,718,424
U.S. government and federal agency securities	0	0
Sovereign obligations	956,992	1,253,754
Loans	1,148,824	801,977
Derivatives	3,399,239	4,856,310
Total financial instruments sold, not yet purchased	7,226,002	8,647,271
Other secured financings		41,350
Short-term borrowings	23,324
Long-term debt	606,956	248,856
Obligation to return securities received as collateral	0
Level 2 \| Residential mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	1,453,294	960,494
Level 2 \| Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	508,115	296,405
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	0
Level 2 \| Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	217,111	63,587
Level 3
Financial instruments owned:
Corporate equity securities	22,009	21,739
Corporate debt securities	26,036	25,005
CDOs and CLOs	30,004	54,354
U.S. government and federal agency securities	0	0
Municipal securities	0	27,257
Sovereign obligations	0	0
Loans and other receivables	47,304	81,872
Derivatives	9,295	6,429
Investments at fair value	93,454	96,369
Total financial instruments owned, excluding Investments at fair value based on NAV	327,727	413,288
Securities received as collateral	0
Financial instruments sold, not yet purchased:
Corporate equity securities	48	313
Corporate debt securities	522	523
U.S. government and federal agency securities	0	0
Sovereign obligations	0	0
Loans	3,486	378
Derivatives	16,041	9,870
Total financial instruments sold, not yet purchased	20,202	11,084
Other secured financings		418
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	26,077	38,772
Level 3 \| Commercial mortgage-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	12,419	20,580
Financial instruments sold, not yet purchased:
Commercial mortgage-backed securities	105
Level 3 \| Other asset-backed securities
Financial instruments owned:
Mortgage- and asset-backed securities, assets	$ 61,129	$ 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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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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Amount of collateralized debt obligations classified as other.

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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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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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