Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ 17,698	$ (17,662)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation, depletion, amortization and accretion	114,331	98,672
Exploration expense	36,193	20,827
Stock-based compensation	7,614	6,131
Net cash for plugging wells	(444)
(Gain) loss on derivative instruments	(40,620)	24,055
Net cash receipts (payments) on settled derivatives	11,072	(7,724)
Gain on sale of assets	(734)	(1,814)
Amortization of deferred financing costs	2,160	1,677
Amortization of debt discount	998	995
Changes in operating assets and liabilities:
Accounts receivable	68,056	(48,601)
Other assets	619	(2,144)
Accounts payable and accrued liabilities	(40,634)	18,989
Net cash provided by operating activities	176,309	93,401
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures for oil and gas properties	(268,768)	(210,612)
Capital expenditures for other property and equipment	(576)	(892)
Proceeds from sale of assets	1,810	10,348
Cash proceeds from merger	12,894
Change in deposits and other long-term assets	(53)
Net cash used in investing activities	(254,693)	(201,156)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	(4,242)	(108)
Repayments of long-term debt	(260)	(381)
Proceeds from revolving credit facility	95,000	99,000
Equity issuance costs	(31)	(307)
Employee tax withholding for settlement of equity compensation awards	(6,511)	(1,261)
Net cash provided by financing activities	83,956	96,943
Net increase (decrease) in cash and cash equivalents	5,572	(10,812)
Cash and cash equivalents at beginning of period	5,959	17,224
Cash and cash equivalents at end of period	11,531	6,412
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest	51,280	49,280
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Asset retirement obligations incurred, including changes in estimate	1,006	388
Additions of other property through debt financing		174
Additions to oil and natural gas properties - changes in accounts payable, accrued liabilities, and accrued capital expenditures	16,583	3,988
Asset acquisition through stock issuance		$ 90,020
BRMR Merger consideration	$ 275,759