BORROWINGS - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Weighted average interest rate		1.56%
Repurchase agreement covenant, minimum stockholders' equity	$ 75
Repurchase agreement covenant, minimum stockholders' equity, percentage of historical stockholders' equity (as a percentage)	50.00%

The amount of total capital as defined in the regulations.

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