CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net income	$ 972	$ 115,882
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	255,772	255,497
Write-down of oil and gas properties	47,130
Accretion expense	21,827	25,012
Deferred income tax provision	3,599	77,001
Settlement of asset retirement obligations	(47,217)	(61,178)
Non-cash stock compensation expense	8,409	7,583
Excess tax benefits		(156)
Non-cash derivative (income) expense	(2,386)	1,626
Non-cash interest expense	12,393	12,384
Change in current income taxes	(6)	(704)
Increase in accounts receivable	(1,805)	(22,277)
(Increase) decrease in other current assets	(10)	2,187
Decrease in inventory		158
Increase (decrease) in accounts payable	(3,547)	8,035
Increase in other current liabilities	37,441	20,251
Other	(172)	(1,791)
Net cash provided by operating activities	332,400	439,510
Cash flows from investing activities:
Investment in oil and gas properties	(727,488)	(472,304)
Proceeds from sale of oil and gas properties, net of expenses	223,299	6,300
Investment in fixed and other assets	(8,790)	(3,830)
Change in restricted funds	(185,752)	(2,394)
Net cash used in investing activities	(698,731)	(472,228)
Cash flows from financing activities:
Net proceeds from issuance of common stock	225,999
Deferred financing costs	(3,329)	(11)
Excess tax benefits		156
Net payments for share-based compensation	(7,161)	(3,733)
Net cash provided by (used in) financing activities	215,509	(3,588)
Effect of exchange rate changes on cash	(95)	(145)
Net change in cash and cash equivalents	(150,917)	(36,451)
Cash and cash equivalents, beginning of period	331,224	279,526
Cash and cash equivalents, end of period	$ 180,307	$ 243,075