CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities
Net loss	$ (17,537)	$ (98,258)
Adjustments to reconcile net loss to net cash provided by operating activities:
Non-cash portion of loss on extinguishment of debt	0	21,822
Depreciation, depletion and amortization	102,557	67,879
Impairments	28,616	71,071
Derivative contracts:
Net gains	(43,521)	(8,329)
Cash settlements	14,951	11,775
Deferred income tax benefit	(10,236)	(54,247)
Gain on sales of property and equipment, net	(834)	(452)
Non-cash exploration expense	16,455	41,081
Non-cash interest expense	2,050	4,750
Share-based compensation (equity-classified)	2,951	3,809
Other, net	203	265
Changes in operating assets and liabilities, net	20,070	2,593
Net cash provided by operating activities	115,725	63,759
Cash flows from investing activities
Capital expenditures - property and equipment	(188,236)	(211,081)
Proceeds from sales of property and equipment, net	527	696
Other, net	180	100
Net cash used in investing activities	(187,529)	(210,285)
Cash flows from financing activities
Dividends paid	(5,176)	(5,156)
Proceeds from revolving credit facility borrowings	84,000	0
Repayment of revolving credit facility borrowings	(3,000)	0
Proceeds From Issuance Of Senior Notes	0	300,000
Repurchase of Convertible Notes	0	(232,963)
Debt issuance costs paid	0	(6,559)
Other, net	0	974
Net cash provided by financing activities	75,824	56,296
Net increase (decrease) in cash and cash equivalents	4,020	(90,230)
Cash and cash equivalents - beginning of period	7,512	120,911
Cash and cash equivalents - end of period	11,532	30,681
Cash paid for:
Interest (net of amounts capitalized)	26,656	19,705
Income taxes (net of refunds received)	$ (311)	$ (96)