VARIABLE INTEREST ENTITIES INTANGIBLE ASSETS (Details) RSO - RSO [Member] - USD ($) $ in Thousands			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			$ 518	$ 517	$ 1,500	$ 1,500
Amortization expense, current	$ 2,000		2,000		2,000
Amortization expense, year two	1,800		1,800		1,800
Amortization expense, year three	1,800		1,800		1,800
Amortization expense, year four	1,600		1,600		1,600
Amortization expense, year five	1,000		1,000		$ 1,000
Weighted average amortization period					6 years		6 years 7 months 6 days
Fee income			1,266	2,344	$ 6,317	7,166
Servicing Contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			1,300	423	3,100	1,100
Amortization expense, year two	3,900		3,900		3,900
Amortization expense, year three	3,800		3,800		3,800
Amortization expense, year four	3,700		3,700		3,700
Amortization expense, year five	$ 3,100		3,100		3,100
Weighted average amortization period	1 year 2 months 12 days	1 year 4 months 24 days
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	$ 4,100		4,100		4,100
Principal Amount Outstanding of Loans Held-in-portfolio	$ 1,753,227	$ 894,767	1,753,227		1,753,227		$ 894,767	$ 433,153
Investment in RCAM [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fee income			$ 791	$ 1,200	$ 2,700	$ 4,000