Investments of Operating Entities and Consolidated Funds - Real Estate Investments (Details) (USD $)	3 Months Ended
Mar. 31, 2014	Dec. 31, 2013
Investment Holdings [Line Items]
Other investments	$ 144,147,000	$ 99,483,000
Real Estate Equity Investment
Investment Holdings [Line Items]
Other investments	42,283,000	2,088,000
Mortgage Loans on Real Estate	40,000,000
Interest rate basis spread	6.00%
RCG RE Manager, LLC \| Real Estate Equity Investment
Investment Holdings [Line Items]
Other investments	$ 2,300,000	$ 2,100,000

Total carrying amount of mortgage loans as of the balance sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant