INCOME TAXES - Expected And Reported Income Taxes (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Federal statutory income tax rate	35.00%	35.00%	35.00%
Federal statutory income tax rate - revised	21.00%
Computed tax expense (benefit) at federal statutory rates on income (loss) before income taxes (benefit)	$ (8,425)	$ 18,501	$ 16,667
State income tax expense (benefit), net of federal benefit	23,045	(5,202)	1,333
Federal tax expense associated with non-amortizable assets	0	0	0
Non recognition of expense due to full valuation allowance	0	0	(244)
Valuation allowance current year activity	2,395	0	0
Decrease in valuation allowance for change in federal net operating loss carryback rules	0	0	0
Change in uncertain tax positions	0	0	0
US federal income tax reform	(291,497)	0	0
Tax impact of share-based awards	1,383	0	0
Transaction costs	8,477	0	0
Recognized gain on Exchange	6,435	0	0
Tax benefit shortfall associated with share-based awards	0	286	12
Nondeductible expenses and other	1,102	1,209	669
Income taxes (benefit)	(257,085)	$ 14,794	$ 18,437
Effective income tax rate		28.00%	38.70%
Impairment loss	$ 952	$ 254	$ 0