INCOME TAXES - Total Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income taxes:
Federal	$ (15)	$ (1,041)	$ 0
State	0	0	0
Total current income taxes	(15)	(1,041)	0
Deferred income taxes:
Federal	67,516	(10,464)	5,413
State	(2,601)	1,004	1,628
Total deferred income taxes	64,915	(9,460)	7,041
Total	$ 64,900	$ (10,501)	$ 7,041