Goodwill and Intangible Assets Schedule of Goodwill by Segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Roll Forward]
Goodwill, Gross	$ 54,591us-gaap_GoodwillGross	$ 45,896us-gaap_GoodwillGross
Goodwill, Impaired, Accumulated Impairment Loss	(17,351)	(17,351)
Goodwill	37,240us-gaap_Goodwill	28,545us-gaap_Goodwill
Goodwill, Acquired During Period	0us-gaap_GoodwillAcquiredDuringPeriod	8,695us-gaap_GoodwillAcquiredDuringPeriod
Goodwill impairment	(2,334)us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Goodwill, Gross	54,591us-gaap_GoodwillGross	54,591us-gaap_GoodwillGross	45,896us-gaap_GoodwillGross
Goodwill, Impaired, Accumulated Impairment Loss	(19,685)	(17,351)	(17,351)
Goodwill	34,906us-gaap_Goodwill	37,240us-gaap_Goodwill	28,545us-gaap_Goodwill
Alternative Investment
Goodwill [Roll Forward]
Goodwill, Gross	30,228	30,228
Goodwill, Impaired, Accumulated Impairment Loss	(10,200)	(10,200)
Goodwill	20,028	20,028
Goodwill, Acquired During Period	0	0
Goodwill impairment	0	0
Goodwill, Gross	30,228	30,228
Goodwill, Impaired, Accumulated Impairment Loss	(10,200)	(10,200)
Goodwill	20,028	20,028
Broker-Dealer
Goodwill [Roll Forward]
Goodwill, Gross	24,363	15,668
Goodwill, Impaired, Accumulated Impairment Loss	(7,151)	(7,151)
Goodwill	17,212	8,517
Goodwill, Acquired During Period	0	8,695
Goodwill impairment	(2,334)	0
Goodwill, Gross	24,363	24,363
Goodwill, Impaired, Accumulated Impairment Loss	(9,485)	(7,151)
Goodwill	$ 14,878	$ 17,212

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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