DERIVATIVE INSTRUMENTS (Schedule of the Company's Derivative Assets and Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 3,873	$ 5,797
Total return swaps
Derivatives, Fair Value [Line Items]
Derivative Asset	776	1,130
Basis swaps
Derivatives, Fair Value [Line Items]
Derivative Asset	665	808
Interest rate caps
Derivatives, Fair Value [Line Items]
Derivative Asset	520	998
Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative Asset	1,733	2,674
Foreign currency forward exchange
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 179	$ 187