Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended
Mar. 31, 2014 ForwardContracts	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities valuation adjustment	$ 8,700,000
Loan position held in secondary loan trading portfolio	0	0
Loans held for sale period	60 days
Fair value of loan held for sale	9,438,000	75,989,000
Book value of loan held for sale	9,700,000
Number of foreign exchange option outstanding	0
Forward or delayed delivery of the underlying instrument with settlement	180 days
Deferred Compensation [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	15,100,000	15,300,000
U.S. Treasury Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of open short contract	330
Open short contract, period	10 years
Futures contracts used as economic hedge	179,000
Federal Funds Futures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Futures contracts used as economic hedge	105,000
Open contracts for Federal Funds futures	1,125
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
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	91,500,000
Commitment to purchase ARS from clients through 2016	5,000,000
ARS held in proprietary trading account result of the failed auctions
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	1,000,000
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	2,100,000
Auction Rate Securities Owned [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Valuation adjustment (unrealized loss) for ARS	6,500,000
Auction Rate Securities Commitments to Purchase [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities valuation adjustment	$ 2,200,000

Assets and liabilities transferred from level one to level two.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Continuous prepayment rate used before specified loans prepayment penalty rate.

+ References

No definition available.

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- Definition

Derivative contract period.

+ References

No definition available.

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- Definition

Estimated future cost to service loans on annual basis per loan average.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Hedge designations used for interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

Loan held for sale period.

+ References

No definition available.

+ Details

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- Definition

Loan position held in secondary loan trading portfolio fair value.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Loans prepayment penalty rate.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Number of foreign exchange options outstanding.

+ References

No definition available.

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- Definition

Open future contracts written number of contracts.

+ References

No definition available.

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- Definition

Securities committed to purchase amount.

+ References

No definition available.

+ Details

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- Definition

Securities committed to purchase period.

+ References

No definition available.

+ Details

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- Definition

Securities purchases against purchase offers and legal settlement.

+ References

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

Us treasury notes open future contracts written number of contracts.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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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

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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

+ References

No definition available.

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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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