INCOME TAXES - Summary of deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Net operating loss carry-forward	$ 31,992	$ 27,568
Share based compensation	531	808
Abandonment obligation	761	541
Derivative instruments	1,526	0
Deferred revenue	15,863	11,630
Interest expense	4,540	3,804
Lease Liability	386
Property Basis	27,837
Accrued liabilities and other	144	85
Total deferred tax asset	83,580	44,436
Valuation allowance	(83,197)	(23,611)
Deferred tax asset, net of valuation allowance	383	20,825
Deferred tax liabilities:
Derivative instruments	0	249
Oil and natural gas properties and equipment	0	20,576
Right of use asset	383
Total deferred tax liability	383	20,825
Net deferred tax asset (liability)	$ 0	$ 0