INCOME TAXES - Reconciliation of Income Tax Computed at Federal Statutory Rate (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended			36 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
INCOME TAXES
Federal statutory rate (as a percent)									19.50%	20.00%	20.70%	21.00%
Increase (Decrease) Resulting from:
Income Tax (Expense) Benefit Computed at Federal Statutory Rate									$ 971	$ (4,410)	$ (4,557)
State Income Tax, Net of Federal Income Tax Benefit									180	(1,076)	(1,363)
Income Tax on Permanently Non-Deductible Items									(112)	(86)	(32)
Tax Benefit due to De-Recognition of REIT Deferred Tax Liabilities									82,460
Other Reconciling Items										100	(73)
Benefit (Expense) for Income Taxes	$ 83,089	$ 501	$ (4,179)	$ 4,088	$ (182)	$ (574)	$ (2,941)	$ (1,775)	$ 83,499	$ (5,472)	$ (6,025)
Federal statutory rate (as a percent)									(19.50%)	(20.00%)	(20.70%)	(21.00%)
State Income Tax, Net of Federal Income Tax Benefit									(3.60%)	(5.00%)	(5.50%)
Income Tax on Permanently Non-Deductible Items									2.20%	(0.40%)	(0.20%)
Tax Benefit due to De-Recognition of REIT									(1652.60%)	0.00%	0.00%
Other Reconciling Items									0.00%	0.50%	(0.30%)
Effective Income Tax Rate Reconciliation, Percent, Total									(1673.40%)	(24.90%)	(26.70%)