DEBT OBLIGATIONS (Details)									3 Months Ended		12 Months Ended
	Oct. 25, 2015 USD ($) Extension	Aug. 14, 2015 USD ($) Extension	Jun. 26, 2015 USD ($)	Apr. 10, 2015 USD ($) Extension	Feb. 19, 2015 Extension	Oct. 31, 2014 USD ($)	Feb. 11, 2014 USD ($) Extension	Jan. 24, 2013 USD ($) Financing_Counterparty	Mar. 31, 2016 USD ($) agreement Extension	Mar. 31, 2015 USD ($) agreement	Dec. 31, 2015 USD ($) Extension	Feb. 19, 2016
Debt Instrument [Line Items]
Amortization of premiums									$ (216,000)	$ (192,000)
Percent of FHLB advances to total debt obligations outstanding									46.00%
Debt obligations outstanding									$ 1,104,339,000		$ 1,260,755,000
Restricted equity from payment as dividend									900,300,000
Tuebor
Debt Instrument [Line Items]
Amount restricted from transfer									451,900,000
Revolving credit facility | One-Month LIBOR
Debt Instrument [Line Items]
Committed amount on credit agreement							$ 143,000,000
Debt borrowings term							3 years
Number of extension maturity periods | Extension							2
Length of extension options							12 months
Basis spread on variable rate (as a percent)							3.50%
Letters of credit
Debt Instrument [Line Items]
Committed amount on credit agreement							$ 25,000,000
Term master repurchase agreement
Debt Instrument [Line Items]
Committed amount on master repurchase agreement									$ 300,000,000
Number of extension executed | Extension					1
Committed loan repurchase facility
Debt Instrument [Line Items]
Number of agreements | agreement									4
Committed amount on master repurchase agreement									$ 1,485,000,000		1,485,000,000
Debt obligations outstanding									$ 535,588,000		704,149,000
Uncommitted securities repurchase facilities | Minimum
Debt Instrument [Line Items]
Advance rates (as a percent)									65.00%
Uncommitted securities repurchase facilities | Maximum
Debt Instrument [Line Items]
Advance rates (as a percent)									95.00%
1/2016 | Uncommitted securities repurchase facilities
Debt Instrument [Line Items]
Debt obligations outstanding											$ 394,719,000
1/2016 | Uncommitted securities repurchase facilities | Minimum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)											0.73%
1/2016 | Uncommitted securities repurchase facilities | Maximum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)											2.02%
5/24/2016 | Committed loan repurchase facility
Debt Instrument [Line Items]
Committed amount on master repurchase agreement									$ 450,000,000		$ 450,000,000
Number of extension maturity periods | Extension									2
Length of extension options									12 months
Debt obligations outstanding									$ 148,731,000		$ 269,779,000
5/24/2016 | Committed loan repurchase facility | Minimum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									2.69%		2.58%
5/24/2016 | Committed loan repurchase facility | Maximum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									4.36%		4.33%
5/24/2016 | Committed loan repurchase facility | Consolidated Subsidiaries
Debt Instrument [Line Items]
Debt obligations outstanding									$ 22,900,000		$ 28,200,000
4/10/2019 | Term master repurchase agreement
Debt Instrument [Line Items]
Number of extension executed | Extension				1
4/9/2017 | Committed loan repurchase facility
Debt Instrument [Line Items]
Committed amount on master repurchase agreement				$ 400,000,000					$ 400,000,000
Number of extension maturity periods | Extension									2
Length of extension options									364 days
Debt obligations outstanding									$ 176,746,000
4/9/2017 | Committed loan repurchase facility | Minimum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									2.68%
4/9/2017 | Committed loan repurchase facility | Maximum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									4.44%
4/9/2017 | Committed loan repurchase facility | Consolidated Subsidiaries
Debt Instrument [Line Items]
Debt obligations outstanding									$ 32,200,000
10/30/2016 | Committed loan repurchase facility
Debt Instrument [Line Items]
Committed amount on master repurchase agreement		$ 600,000,000							$ 600,000,000		$ 600,000,000
Number of extension executed | Extension		1
Number of extension maturity periods | Extension									2		2
Length of extension options									12 months		12 months
Debt obligations outstanding									$ 207,849,000		$ 229,533,000
10/30/2016 | Committed loan repurchase facility | Minimum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									2.19%		2.08%
10/30/2016 | Committed loan repurchase facility | Maximum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									2.94%		2.93%
10/24/2016 | Committed loan repurchase facility
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)											3.02%
Committed amount on master repurchase agreement	$ 35,000,000								$ 35,000,000		$ 35,000,000
Number of extension maturity periods | Extension	2								2		2
Length of extension options	6 months								6 months		6 months
Debt obligations outstanding									$ 2,262,000		$ 575,000
10/24/2016 | Committed loan repurchase facility | Minimum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									3.03%
10/24/2016 | Committed loan repurchase facility | Maximum
Debt Instrument [Line Items]
Interest Rate(s) (as a percent)									3.04%
10/24/2016 | Committed loan repurchase facility | Consolidated Subsidiaries
Debt Instrument [Line Items]
Debt obligations outstanding									$ 3,200,000		800,000
Credit Agreement
Debt Instrument [Line Items]
Committed amount on credit agreement								$ 50,000,000
Number of multiple committed financing counterparties | Financing_Counterparty								1
Credit Agreement | One-Month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)								2.75%
Mortgage loan financing
Debt Instrument [Line Items]
Number of agreements | agreement									4	14
Stated interest rate, minimum (as a percent)									4.25%
Borrowing under credit and security agreement									$ 547,800,000
Stated interest rate, maximum (as a percent)									6.75%
Mortgage loan financing											544,700,000
Net unamortized premiums									$ 6,000,000		6,100,000
Amortization of premiums									200,000	$ 200,000
Pledged assets, real estate and lease intangibles, net									$ 712,500,000		$ 711,100,000
Borrowings from the Federal Home Loan Bank | Tuebor
Debt Instrument [Line Items]
Debt borrowings term									8 years		8 years
Stated interest rate, minimum (as a percent)									0.38%		0.28%
Stated interest rate, maximum (as a percent)									2.74%		2.74%
Weighted average interest rate									0.97%		0.84%
Weighted average term									2 years 6 months 10 days		1 year 5 months 1 day
Maximum advance limit			$ 2,900,000,000
FHLB borrowings outstanding									$ 1,900,000,000		$ 1,900,000,000
Additional committed term financing available from FHLB									$ 340,800,000		$ 380,400,000
Maximum percent of FHLB advances to total assets												40.00%
Borrowings from the Federal Home Loan Bank | Tuebor | Ladder Capital Corp
Debt Instrument [Line Items]
Advance rates of total assets (as a percent)			40.00%
Advance rates of total equity (as a percent)			150.00%
Borrowings from the Federal Home Loan Bank | Tuebor | Minimum
Debt Instrument [Line Items]
Advance rates (as a percent)									50.00%		58.70%
Borrowings from the Federal Home Loan Bank | Tuebor | Maximum
Debt Instrument [Line Items]
Advance rates (as a percent)									95.20%		95.20%
Borrowings from the Federal Home Loan Bank | Tuebor | CMBS and U.S. Agency Securities
Debt Instrument [Line Items]
Collateral for debt instrument									$ 1,800,000,000		$ 1,700,000,000
Borrowings from the Federal Home Loan Bank | Tuebor | First mortgage commercial real estate loans
Debt Instrument [Line Items]
Collateral for debt instrument									507,700,000		568,200,000
Credit and Security Agreement
Debt Instrument [Line Items]
Debt instrument, aggregate amount						$ 46,750,000
Credit and Security Agreement | One-Month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						1.85%
Credit Agreement and Revolving Credit Facility
Debt Instrument [Line Items]
Unamortized debt issuance costs									$ 2,300,000		$ 3,400,000