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The amount of identifiable intangible assets recognized as of the acquisition date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Goodwill and Intangible Assets Schedule of Intangible Assets (Details) (Annual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 34,064,000	$ 38,704,000
Intangible assets, accumulated amortization (in dollars)	(25,581,000)	(26,610,000)
Intangible Assets, Net	8,483,000	12,094,000
Amortization of Intangible Assets	3,600,000us-gaap_AmortizationOfIntangibleAssets	3,700,000us-gaap_AmortizationOfIntangibleAssets	2,700,000us-gaap_AmortizationOfIntangibleAssets
Investment Contracts
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Finite-Lived Intangible Assets, Gross	3,900,000	3,900,000
Intangible assets, accumulated amortization (in dollars)	(3,900,000)	(3,900,000)
Intangible Assets, Net	0	0
Trade Names
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	9,612,000	9,612,000
Intangible assets, accumulated amortization (in dollars)	(8,305,000)	(7,747,000)
Intangible Assets, Net	1,307,000	1,865,000
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	13,284,000	14,744,000
Intangible assets, accumulated amortization (in dollars)	(8,936,000)	(8,375,000)
Intangible Assets, Net	4,348,000	6,369,000
Customer Contracts
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year 2 months 12 days
Finite-Lived Intangible Assets, Gross	800,000	800,000
Intangible assets, accumulated amortization (in dollars)	(800,000)	(800,000)
Intangible Assets, Net	0	0
Noncompete agreements and covenants with limiting conditions acquired
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	31,000	2,697,000
Intangible assets, accumulated amortization (in dollars)	(21,000)	(2,583,000)
Intangible Assets, Net	10,000	114,000
Intellectual property
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	6,437,000	6,951,000
Intangible assets, accumulated amortization (in dollars)	(3,619,000)	(3,205,000)
Intangible Assets, Net	2,818,000	3,746,000
Dahlman Rose & Company, LLC
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	2,800,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years 8 months 1 day
Cowen Equity Finance
Acquired Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived	$ 900,000
Minimum \| Trade Names
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Minimum \| Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	4 years
Minimum \| Noncompete agreements and covenants with limiting conditions acquired
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year
Minimum \| Intellectual property
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Maximum \| Trade Names
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	7 years 6 months
Maximum \| Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum \| Noncompete agreements and covenants with limiting conditions acquired
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum \| Intellectual property
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years