DERIVATIVES - Schedule of Derivatives - Gain (Losses) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Derivative [Line Items]
Unrealized gain (loss) on derivative instruments	[1]	$ 4,326	$ (24,557)
Gain (loss) on settlement of derivatives		(11,836)	(30,379)
Total income (losses)		(7,510)	(54,936)
TBAs [Member]
Derivative [Line Items]
Unrealized gain (loss) on derivative instruments	[1]	123	(5,531)
Gain (loss) on settlement of derivatives		(6,801)	(28,171)
Interest Rate Caps [Member]
Derivative [Line Items]
Unrealized gain (loss) on derivative instruments	[1]	573	(951)
Gain (loss) on settlement of derivatives		(562)	(1,124)
Interest Rate Swap [Member]
Derivative [Line Items]
Unrealized gain (loss) on derivative instruments	[1]	3,630	(18,075)
Gain (loss) on settlement of derivatives		$ (4,473)	$ (1,084)

[1] Represents unrealized gains (losses).