INCOME TAXES - Operating Loss and Tax Credit Carryforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Carryforwards
Taxable income	$ 46,400
Valuation allowance	$ 30,468
Federal income tax expense at statutory rate	21.00%	21.00%	35.00%
Effect of Tax Cuts and Jobs Act of 2017
Income tax benefit for remeasurement of deferred tax from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017			$ 17,200
Federal
Carryforwards
Net operating loss carryforwards	$ 492,500
State
Carryforwards
Net operating loss carryforwards	356,200
Alternative Minimum Tax Credit Carryforwards
Carryforwards
Tax credit carryforwards	$ 300