VARIABLE INTEREST ENTITIES - Schedule of the Fair Value of OBX Trusts Closed (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Jul. 31, 2019	Jun. 30, 2019	Apr. 30, 2019	Jan. 31, 2019	Dec. 31, 2018	[2]	Oct. 31, 2018	Jul. 31, 2018	Mar. 31, 2018
Variable Interest Entity [Line Items]
Loans	[1]	$ 3,946,614					$ 4,585,975
OBX Trust | Consolidated VIEs
Variable Interest Entity [Line Items]
Loans			$ 463,405	$ 383,760	$ 388,156	$ 393,961			$ 384,027	$ 383,451	$ 327,162

[1] ⁽⁴⁾  Includes $76.3 million and $97.5 million of residential mortgage loans held for sale and $0 and $42.2 million of commercial mortgage loans held for sale at September 30, 2019 and December 31, 2018, respectively.

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