Fair Value Measurements - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2013 ForwardContracts	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan position held in secondary loan trading portfolio	$ 0	$ 0
Fair value of the reverse repurchase agreements	184,000,000
Fair value of the repurchase agreements	0
Loans held for sale period	60 days
Fair value of loan held for sale	75,989,000
Book value of loan held for sale	74,200,000
Derivatives instruments gain recognized income		28,000
Number of foreign exchange option outstanding	0
Forward or delayed delivery of the underlying instrument with settlement	180 days
Auction Rate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities valuation adjustment	9,100,000
Auction Rate Securities Owned other [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities valuation adjustment	6,500,000
ARS Purchase Commitments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities valuation adjustment	2,600,000
Deferred Compensation Share Based Payments [Member] \| Corporate Equities Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of the corporate equities that are included in securities owned	15,300,000	14,000,000
Senior Secured Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate	8.75%
Auction Rate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Company purchased and holds auction rate securities	91,600,000
Commitment to purchase ARS from clients through 2016	29,100,000
ARS held in proprietary trading account result of the failed auctions	150,000
Valuation adjustment (unrealized loss) for ARS	6,500,000
Assets and liabilities transferred from level one and level two	0
Auction Rate Securities [Member] \| Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitment to purchase ARS period maximum	2016
Auction Rate Securities [Member] \| Range One [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Basis point	0.25%
Decrease in fair value of ARS	1,900,000
Decrease in fair value of ARS correspond to reduction in duration	1,900,000
Auction Rate Securities [Member] \| Range Two [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Basis point	0.50%
Decrease in fair value of ARS	3,800,000
Decrease in fair value of ARS correspond to reduction in duration	2,000,000
Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Permanent and construction loans , discount rate	12.00%
Continuous prepayment rate used up to loans prepayment penalty rate hit 4%	0.00%
Continuous prepayment rate	4.00%
Continuous prepayment rate vast majority range maximum	15.00%
Continuous prepayment rate vast majority range minimum	10.00%
Continuous prepayment rate vast majority range average rate	12.00%
Estimated future cost to service loans on an annual basis per loan, average	1,250
U.S. Treasury Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of open short contract	400
Open short contract, period	10 years
Futures contracts used as economic hedge	186,000
Federal Funds Futures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Futures contracts used as economic hedge	$ 18,000
Open contracts for Federal Funds futures	1,231

Assets and liabilities transferred from level one to level two.

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ARS in firm's proprietary account as a result of the failed auctions.

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Continuous prepayment rate used after specified loans prepayment penalty rate average.

+ References

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Continuous prepayment rate used after specified loans prepayment penalty rate maximum.

+ References

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- Definition

Continuous prepayment rate used after specified loans prepayment penalty rate minimum.

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Continuous prepayment rate used before specified loans prepayment penalty rate.

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- Definition

Derivative contract period.

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No definition available.

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- Definition

Fair value of corporate equities that are included in securities owned.

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- Definition

Fair value of securities repurchase agreement.

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- Definition

Fair value of securities reverse repurchase agreement.

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- Definition

Hedge designations used for interest rate derivatives.

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- Definition

Loan held for sale period.

+ References

No definition available.

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- Definition

Loan position held in secondary loan trading portfolio fair value.

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- Definition

The carrying value, as of the balance sheet date, of loans held for sale.

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- Definition

Loans prepayment penalty rate.

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- Definition

Maximum settlement period in case of delayed delivery of underlying instrument.

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No definition available.

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- Definition

Number of foreign exchange options outstanding.

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- Definition

Open future contracts written number of contracts.

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- Definition

Securities committed to purchase amount.

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Securities committed to purchase period.

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- Definition

Securities purchases against purchase offers and legal settlement.

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- Definition

Sensitivity analysis of fair value of interests continued to be held by transferor servicing assets or liabilities change in discount rate.

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- Definition

Sensitivity analysis of fair value of interests continued to be held by transferor servicing assets or liabilities impact of other than ten or twenty percent adverse change in security duration.

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- Definition

Us treasury notes open future contracts written number of contracts.

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- Definition

Valuation adjustment for the level 3 assets used for quantitative disclosure.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.22(a)(1))

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Amount of increase in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

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- Definition

The loan servicing fees paid to third parties that relate to loan expenses for a portfolio containing the entire group of loans owned by the company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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- Definition

The hypothetical financial impact of a specified adverse percentage change in discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (c)

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