Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ (66,024)	$ 13,414
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation, depletion, amortization and accretion	87,244	68,708
Exploration expense	19,359	22,206
Stock-based compensation	2,624	6,553
Impairment of oil and gas properties	6,849
Net cash for plugging wells	(102)	(214)
Gain on derivative instruments	(29,207)	(24,808)
Net cash receipts (payments) on settled derivatives	43,092	(746)
Gain on sale of assets	(1,419)	(6)
Amortization of deferred financing costs	1,432	1,201
Amortization of debt discount	667	665
Changes in operating assets and liabilities:
Accounts receivable	18,861	52,182
Other assets	(710)	(15)
Accounts payable and accrued liabilities	(40,539)	(56,047)
Net cash provided by operating activities	42,127	83,093
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures for oil and gas properties	(76,459)	(177,334)
Capital expenditures for other property and equipment	(254)	(193)
Proceeds from sale of assets	1,335	16
Cash acquired in merger		12,894
Change in deposits and other long-term assets		(53)
Net cash used in investing activities	(75,378)	(164,670)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from other notes payable	1,141
Debt issuance costs	(80)	(3,361)
Repayments of long-term debt	(182)	(182)
Proceeds from revolving credit facility	30,000	95,000
Equity issuance costs		(31)
Employee tax withholding for settlement of equity compensation awards	(463)	(6,360)
Net cash provided by financing activities	30,416	85,066
Net increase (decrease) in cash and cash equivalents	(2,835)	3,489
Cash and cash equivalents at beginning of period	12,056	5,959
Cash and cash equivalents at end of period	9,221	9,448
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest	26,771	25,884
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Asset retirement obligations incurred, including changes in estimate	138	750
Additions to oil and natural gas properties - changes in accounts payable, accrued liabilities, and accrued capital expenditures	$ 4,649	41,668
BRMR Merger consideration		$ 275,759