SUPPLEMENTAL NON-CASH TRANSACTIONS - Summary of supplemental disclosure of cash flow information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Non-cash investing and financing activities excluded from the statement of cash flows:
Issued shares of common stock and preferred stock upon extinguishment of debt and modification of Series C Preferred Stock and Series D Preferred Stock	$ 141,787	$ 64,504
Common stock issued for acquisition of oil and natural gas properties	0	24,778
Cashless exercise of warrants	0	359
Deferred revenue realized upon purchase option exercise	16,700	0
Right of use assets obtained in exchange for operating lease obligations	7,500	0
Change in capital expenditures for drilling costs in accrued liabilities	2,010	7,850
Accrued cumulative paid in kind dividends on preferred stock	25,397	10,687
Change in asset retirement obligations	546	1,495
Reduction of fair value for converted embedded derivatives	0	12,406
Transfer of warrant derivative instruments to equity	$ 0	$ 223