SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		May 01, 2019	Apr. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	[2]
Subsequent Event [Line Items]
Residential mortgages loans	[1]			$ 3,879,324	$ 4,585,975
Preferred stock, redemption price (in dollars per share)				$ 25.00
Subsequent Event
Subsequent Event [Line Items]
Preferred stock, redemption price (in dollars per share)		$ 25.00
OBX 2019-EXP1 | Consolidated VIEs | Subsequent Event
Subsequent Event [Line Items]
Residential mortgages loans			$ 388,200
Series H Preferred Stock | Subsequent Event
Subsequent Event [Line Items]
Preferred stock to be redeemed (in shares)		2.2

[1] (4) Includes $101.3 million and $97.5 million of residential mortgage loans held for sale, $42.0 million and $42.2 million of commercial mortgage loans held for sale and $44.5 million and $0 of corporate loans held for sale at March 31, 2019 and December 31, 2018, respectively.

[2] (1) Derived from the audited consolidated financial statements at December 31, 2018.