CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities
Net income (loss)	$ (283,780)	$ (69,836)	$ 279,370
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depletion, depreciation and amortization	150,608	166,290	208,628
Deferred income taxes	(23,561)	110,786	216,409
Unsuccessful well costs	6,079	94,910	1,105
Change in fair value of derivatives	46,559	(210,957)	(271,298)
Cash settlements on derivatives, net (including $187.9 million, $225.5 million and $18.4 million on commodity hedges during 2016, 2015 and 2014)	188,895	224,741	4,460
Equity-based compensation	40,084	75,057	79,541
Gain on sale of assets		(24,651)	(23,769)
Loss on extinguishment of debt		165	2,898
Other	13,355	7,875	(3,875)
Changes in assets and liabilities:
(Increase) decrease in receivables	(20,558)	2,209	(156,192)
Increase in inventories	(4,107)	(29,855)	(8,100)
(Increase) decrease in prepaid expenses and other	17,557	512	1,732
Increase (decrease) in accounts payable	(75,487)	111,289	90,228
Increase (decrease) in accrued liabilities	(3,567)	(17,756)	22,449
Net cash provided by (used in) operating activities	52,077	440,779	443,586
Investing activities
Oil and gas assets	(535,975)	(823,642)	(424,535)
Other property	(1,998)	(1,483)	(2,383)
Proceeds on sale of assets	210	28,692	58,315
Net cash used in investing activities	(537,763)	(796,433)	(368,603)
Financing activities
Borrowings under long-term debt	450,000	100,000
Payments on long-term debt		(200,000)	(400,000)
Net proceeds from issuance of senior secured notes		206,774	294,000
Purchase of treasury stock	(1,981)	(18,110)	(11,096)
Deferred financing costs		(9,030)	(22,088)
Net cash provided by (used in) financing activities	448,019	79,634	(139,184)
Net decrease in cash, cash equivalents and restricted cash	(37,667)	(276,020)	(64,201)
Cash, cash equivalents and restricted cash at beginning of period	310,862	586,882	651,083
Cash, cash equivalents and restricted cash at end of period	273,195	310,862	586,882
Cash paid for:
Interest	27,860	33,315	23,182
Income taxes	13,997	$ 35,857	$ 108,068
Non-cash activity:
Conversion of joint interest billings receivable to long-term note receivable	$ 9,814