Fair Value Measurements - Narrative (Details) - Investments [Domain] - USD ($)	6 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Company purchased and holds auction rate securities	$ 107,600,000
Commitment to purchase ARS from clients through 2016	16,700,000
Valuation adjustment (unrealized loss) for ARS	8,225,000
Fair value of the reverse repurchase agreements	$ 104,301,000	$ 250,000,000
Loans held for sale period	60 days
Fair value of loan held for sale	$ 76,351,000	19,243,000
Book value of loan held for sale	$ 71,200,000
Forward or delayed delivery of the underlying instrument with settlement	180 days
Auction Rate Securities Owned [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Valuation adjustment (unrealized loss) for ARS	$ 7,191,000
LIBOR or Treasury Yield [Member] \| Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction market preferred securities variable interest rate earned	200.00%
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	$ 14,300,000	$ 15,700,000
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 minimum	10.00%
Continuous prepayment rate vast majority range maximum	15.00%
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] \| Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commitment to purchase ARS period maximum	2017
Auction Rate Securities Purchase Commitment [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Valuation adjustment (unrealized loss) for ARS	$ 1,034,000
Fair Value, Valuation Scenario Two [Member] \| Auction Rate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Sensitivity Analysis Of Fair Value Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities Change In Discount Rate	0.50%
Decrease in fair value of ARS	$ 2,100,000
Fair Value, Valuation Scenario One [Member] \| Auction Rate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Sensitivity Analysis Of Fair Value Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities Change In Discount Rate	0.25%
Decrease in fair value of ARS	$ 1,100,000

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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Continuous prepayment rate used before specified loans prepayment penalty rate.

+ 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

Fair value of securities reverse repurchase agreement.

+ References

No definition available.

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- Definition

Loan held for sale period.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Securities committed to purchase amount.

+ References

No definition available.

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- Definition

Securities committed to purchase period.

+ References

No definition available.

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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.

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- Definition

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

+ References

No definition available.

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- Definition

The interest (or dividend) rates earned on action market preferred securities (on an annual basis or APY) for the period reported.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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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 FASB

-Name Accounting Standards Codification

-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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

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

+ References

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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)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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