Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (14,098)	$ (2,626)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities
Depreciation, depletion, amortization and accretion	29,950	31,311
Exploration expense	9,600	6,790
Stock-based compensation	6,001	1,981
Net cash for plugging wells	(48)
Loss on derivative instruments	4,931	4,215
Net cash receipts (payments) on settled derivatives	(3,186)	141
(Gain) loss on sale of assets	2	(267)
Amortization of deferred financing costs	629	554
Amortization of debt discount	333	332
Changes in operating assets and liabilities:
Accounts receivable	25,812	(35,499)
Other assets	(188)	(459)
Accounts payable and accrued liabilities	(68,643)	(3,179)
Net cash provided by (used in) operating activities	(8,905)	3,294
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures for oil and gas properties	(58,530)	(66,441)
Capital expenditures for other property and equipment	(184)	(155)
Proceeds from sale of assets	1	4,099
Cash proceeds from merger	12,894
Change in deposits and other long term assets	(3)
Net cash used in investing activities	(45,822)	(62,497)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	(3,102)	(48)
Repayments of long-term debt	(98)	(92)
Proceeds (repayments) from revolving credit facility	65,000	65,000
Equity issuance costs	(30)	(145)
Employee tax withholding for settlement of equity compensation awards	(5,410)	(935)
Net cash provided by financing activities	56,360	63,780
Net increase in cash and cash equivalents	1,633	4,577
Cash and cash equivalents at beginning of period	5,959	17,224
Cash and cash equivalents at end of period	7,592	21,801
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest	24,198	23,638
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Asset retirement obligations incurred, including changes in estimate	16,691	85
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	45,287	8,864
Asset acquisition through stock issuance		$ 90,020
BRMR Merger consideration	$ 275,759