Credit concentration receivable from major broker dealers.

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- Definition

Margin deposited with option clearing corporation.

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- Definition

Fair value of loans collateralized by customer securities.

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No definition available.

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Fair value of loans collateralized by firm.

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No definition available.

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Mortgage loan guarantee period.

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No definition available.

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- Definition

Pledged securities owned and pledged as collateral amount eligible to be repledged by counterparty carrying value.

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No definition available.

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- Definition

Receivables from Brokers-Dealers and Clearing Organizations, Number of Major Broker-Dealers

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No definition available.

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- Definition

Securities owned and pledged as collateral amount not eligible to be repledged by counterparty carrying value.

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No definition available.

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Settlement with Financial Institution, Period to Complete Transactions

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Amounts due on short-term bank loans secured by customers' securities on the balance sheet date.

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No definition available.

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- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
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Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it has sold or re-pledged to counterparties as collateral.

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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.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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-Name Regulation S-X (SX)
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-Section 03
-Paragraph 13
-Article 9

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Collateralized Transactions - Narrative (Details)	3 Months Ended		6 Months Ended
Collateralized Transactions - Narrative (Details)	Jun. 30, 2016 USD ($) broker-dealer	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) broker-dealer	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Bank call loans	$ 151,900,000		$ 151,900,000		$ 100,200,000
Customer securities under customer margin loans available to be pledged	1,100,000,000		1,100,000,000
Customer securities under customer margin loans agreement available to be repledged	96,300,000		96,300,000
Customer securities deposited to secure obligations and margin requirements under option contracts	343,100,000		343,100,000
Carrying value of pledged securities owned that can be sold or re-pledged by the counterparty	657,500,000		657,500,000		546,300,000
Carrying value of securities owned by the Company loaned or pledged	$ 173,000,000		$ 173,000,000		142,700,000
Receivable from brokers and clearing organizations, number of major broker-dealers \| broker-dealer	2		2
Receivable from brokers and clearing organizations	$ 107,900,000		$ 107,900,000
Nonrecurring [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warehouse Agreement Borrowings	1,486,000		$ 1,486,000		54,300,000
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Settlement with Financial Institution, Period to Complete Transactions			1 day
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Settlement with Financial Institution, Period to Complete Transactions			3 days
Credit Concentration Risk [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Guaranteed mortgages for a period			15 days
Variable interest rate under warehouse facility			one month LIBOR
Interest expense	159,000	$ 385,000	$ 359,000	$ 510,000
Securities Borrowed Transactions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Customer securities under customer margin loans agreement available to be repledged	26,200,000		26,200,000		36,000,000
Securities received as collateral under securities borrowed transaction with market value	211,100,000		211,100,000		217,000,000
Reverse Repurchase Agreements [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Customer securities under customer margin loans agreement available to be repledged	232,400,000		232,400,000		278,800,000
Securities received as collateral under securities borrowed transaction with market value	232,400,000		232,400,000		$ 278,800,000
Corporate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateralized loans, collateralized by firm	173,000,000		173,000,000
Other Than Corporate Customer [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateralized loans, collateralized by customer securities	$ 171,600,000		$ 171,600,000