Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended
Feb. 28, 2015	Feb. 28, 2014	Nov. 30, 2014
Related Party Transaction [Line Items]
Purchase commitments from Berkadia Commercial Mortgage, LLC	$ 356,400,000	$ 344,800,000
Commissions for conducting brokerage services	166,922,000us-gaap_BrokerageCommissionsRevenue	162,063,000us-gaap_BrokerageCommissionsRevenue
Loans outstanding to certain employees	23,300,000		20,100,000
Noncontrolling interests	39,719,000us-gaap_MinorityInterest		38,848,000us-gaap_MinorityInterest
Leucadia [Member]
Related Party Transaction [Line Items]
Noncontrolling interests	26,000,000		25,400,000
Private Equity Related Funds [Member]
Related Party Transaction [Line Items]
Equity investments loans in related funds	35,900,000		60,700,000
Leucadia [Member]
Related Party Transaction [Line Items]
Revenue from related parties	5,100,000	8,000,000
Due to related party	1,200,000		41,500,000
Due from related party	14,200,000		10,900,000
National Beef Packaging Company, LLC [Member]
Related Party Transaction [Line Items]
Due to related party	5,700,000		4,100,000
Commissions for conducting brokerage services	200,000
Harbinger Group Inc [Member]
Related Party Transaction [Line Items]
Unsettled purchases and sales of loans	248,100,000		232,000,000
Revenue from related parties	$ 400,000

Equity investments in and loans to related funds, in aggregate.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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- Definition

Amount of commission revenue from buying and selling securities on behalf of customers.

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Cost of investments in equity securities and other forms of securities that provide ownership interests classified as trading.

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