Investments - Carrying Value of Investments in Merchant Banking Funds (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Investments in and Advances to Affiliates [Line Items]
Investments in merchant banking funds	$ 6,259	$ 11,745
GCP I
Investments in and Advances to Affiliates [Line Items]
Investments in merchant banking funds	2,029	2,257
GCP II
Investments in and Advances to Affiliates [Line Items]
Investments in merchant banking funds	2,432	7,690
Other Merchant Banking Funds
Investments in and Advances to Affiliates [Line Items]
Investments in merchant banking funds	$ 1,798	$ 1,798

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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 210.5-02.12)

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

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