Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (44,141)	$ 13,288
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depletion, depreciation and amortization	46,603	50,722
Impairment of oil and gas properties	36,059
Right of use asset depreciation	1,193	1,252
Gain on derivatives not designated as hedges	(4,408)	(15,010)
Net cash received in settlement of derivative instruments	15,192	9,560
Share-based compensation (non-cash)	4,827	6,400
Loss on early extinguishment of debt		1,846
Amortization of finance cost, debt discount, paid-in-kind interest and accretion	3,019	7,097
Loss from material transfers & inventory sales & write-downs	104	327
Change in assets and liabilities:
Accounts receivable, trade and other, net of allowance	604	6
Accrued oil and natural gas revenue	1,166	3,119
Inventory		35
Prepaid expenses and other	(116)	(45)
Accounts payable	1,463	614
Accrued liabilities	(2,674)	(140)
Net cash provided by operating activities	58,891	79,071
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(58,262)	(99,301)
Proceeds from sale of assets		1,334
Net cash used in investing activities	(58,262)	(97,967)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments of bank borrowings	(6,000)	(49,500)
Proceeds from bank borrowings	9,500	115,400
Repayment of 2019 Second Lien Notes		(56,728)
Proceeds from 2021/2022 Second Lien Notes		12,000
Issuance cost, net		(2,795)
Other, including purchase of treasury stock	(4,221)	(2,097)
Net cash provided by (used in) financing activities	(721)	16,280
Decrease in cash and cash equivalents	(92)	(2,616)
Cash and cash equivalents, beginning of period	1,452	4,068
Cash and cash equivalents, end of period	1,360	1,452
Supplemental disclosures of cash flow information:
Cash paid during the year for interest	4,030	4,137
Decrease in non-cash capital expenditures	$ (2,037)	$ (1,911)