Condensed Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
OPERATING ACTIVITIES:
Net income (loss)	$ 24,988	$ (113,285)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion, and amortization	97,012	108,468
Impairments (Note 2)	0	112,120
Amortization of debt issuance cost and debt discount	1,075	1,054
(Gain) loss on derivatives	(23,633)	11,743
Cash (payments) receipts on derivatives settled	(1,569)	12,192
Deferred tax expense (benefit)	20,315	(58,560)
Gain on disposition of assets	(1,072)	(946)
Employee stock compensation plans	8,066	7,703
Other, net	299	(2,755)
Changes in operating assets and liabilities increasing (decreasing) cash:
Accounts receivable	(15,087)	5,443
Accounts payable	3,724	24,077
Material and supplies	49	241
Accrued liabilities	756	3,411
Income taxes	(15)	18,969
Other, net	2,147	2,841
Net cash provided by operating activities	117,055	132,716
INVESTING ACTIVITIES:
Capital expenditures	(107,933)	(124,182)
Producing properties and other acquisitions (Note 3)	(52,956)	0
Proceeds from disposition of assets	19,556	46,627
Other	(1,500)	169
Net cash used in investing activities	(142,833)	(77,386)
FINANCING ACTIVITIES:
Borrowings under credit agreement	160,600	150,300
Payments under credit agreement	(156,500)	(195,300)
Payments on capitalized leases	(1,901)	(1,828)
Proceeds from common stock issued, net of issue costs (Note 13)	18,623	0
Tax benefit from stock compensation	0	(376)
Book overdrafts	4,912	(7,987)
Net cash provided by (used in) financing activities	25,734	(55,191)
Net increase (decrease) in cash and cash equivalents	(44)	139
Cash and cash equivalents, beginning of period	893	835
Cash and cash equivalents, end of period	849	974
Cash paid during the year for:
Interest paid (net of capitalized)	16,813	19,830
Income taxes	0	0
Changes in accounts payable and accrued liabilities related to purchases of property, plant, and equipment	(8,771)	30,758
Non-cash reductions to oil and natural gas properties related to asset retirement obligations	$ 1,579	$ 28,884