Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
OPERATING ACTIVITIES:
Net loss	$ (41,149)	$ (248,354)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion, and amortization	56,116	103,590
Impairment of oil and natural gas properties (Note 2)	37,829	400,593
Gain on derivatives	(10,929)	(6,586)
Cash receipts on derivatives settled	7,140	11,012
Deferred tax benefit	(15,718)	(150,643)
Gain on disposition of assets	(469)	(545)
Employee stock compensation plans	4,798	5,863
Other, net	(1,269)	1,374
Changes in operating assets and liabilities increasing (decreasing) cash:
Accounts receivable	10,003	51,910
Accounts payable	11,013	(3,131)
Material and supplies	262	(2,387)
Accrued liabilities	10,702	(6,295)
Other, net	2,384	3,908
Net cash provided by operating activities	70,713	160,309
INVESTING ACTIVITIES:
Capital expenditures	(76,035)	(233,412)
Proceeds from disposition of assets	38,380	2,385
Other	169	0
Net cash used in investing activities	(37,486)	(231,027)
FINANCING ACTIVITIES:
Borrowings under credit agreement	75,000	224,399
Payments under credit agreement	(95,800)	(153,100)
Payments on capitalized leases	(910)	(874)
Tax expense from stock compensation	(376)	0
Book overdrafts	(11,237)	108
Net cash (used in) provided by financing activities	(33,323)	70,533
Net decrease in cash and cash equivalents	(96)	(185)
Cash and cash equivalents, beginning of period	835	1,049
Cash and cash equivalents, end of period	739	864
Cash paid during the year for:
Interest paid (net of capitalized)	(2,024)	(4,475)
Income taxes	0	500
Changes in accounts payable and accrued liabilities related to purchases of property, plant, and equipment	19,685	83,566
Non-cash reductions to oil and natural gas properties related to asset retirement obligations	$ 28,417	$ 6,087