Consolidated balance sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 55,889	$ 112,159
Accounts receivable, net	97,843	100,645
Derivatives	15,442	6,892
Other current assets	16,019	15,686
Total current assets	185,193	235,382
Oil and natural gas properties, full cost method:
Evaluated properties	6,240,743	6,070,940
Unevaluated properties not being depleted	160,097	175,865
Less accumulated depletion and impairment	(4,699,395)	(4,657,466)
Oil and natural gas properties, net	1,701,445	1,589,339
Midstream service assets, net	137,944	138,325
Other fixed assets, net	42,860	40,721
Property and equipment, net	1,882,249	1,768,385
Derivatives	4,541	3,413
Other noncurrent assets, net	15,548	16,109
Total assets	2,087,531	2,023,289
Current liabilities:
Accounts payable and accrued liabilities	88,857	58,341
Accrued capital expenditures	39,385	82,721
Undistributed revenue and royalties	40,393	37,852
Derivatives	17,628	22,950
Other current liabilities	53,403	75,555
Total current liabilities	239,666	277,419
Long-term debt, net	847,300	791,855
Derivatives	325	384
Asset retirement obligations	54,835	53,962
Other noncurrent liabilities	3,575	134,090
Total liabilities	1,145,701	1,257,710
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, 50,000,000 shares authorized and zero issued as of March 31, 2018 and December 31, 2017	0	0
Common stock, $0.01 par value, 450,000,000 shares authorized and 238,320,332 and 242,521,143 issued and outstanding as of March 31, 2018 and December 31, 2017, respectively	2,383	2,425
Additional paid-in capital	2,380,917	2,432,262
Accumulated deficit	(1,441,470)	(1,669,108)
Total stockholders' equity	941,830	765,579
Total liabilities and stockholders' equity	$ 2,087,531	$ 2,023,289