Consolidated statements of cash flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities
Net (loss) income	$ (4,028)	$ 37,710
Adjustments to reconcile net (loss) income to net cash provided by operating activities
Depreciation, depletion & amortization	119,104	91,857
Deferred income taxes	(2,705)	22,007
Gain on hedge reclassification adjustments	0	(19,512)
Non-hedge derivative losses (gains)	87,195	(17,346)
Gain on sale of assets	(811)	(224)
Other	1,670	2,432
Change in assets and liabilities
Accounts receivable	(13,319)	(15,245)
Inventories	(4,908)	(1,568)
Prepaid expenses and other assets	1,463	1,435
Accounts payable and accrued liabilities	(14,560)	(5,912)
Revenue distribution payable	11,233	4,023
Stock-based compensation	2,183	342
Net cash provided by operating activities	182,517	99,999
Cash flows from investing activities
Expenditures for property, plant, and equipment and oil and natural gas properties	(322,310)	(248,206)
Proceeds from asset dispositions	173,175	68,133
Settlement of non-hedge derivative instruments	(21,982)	15,918
Other	0	(664)
Net cash used in investing activities	(171,117)	(164,819)
Cash flows from financing activities
Proceeds from long-term debt	111,282	100,650
Repayment of long-term debt	(134,681)	(33,623)
Principal payments under capital lease obligations	(1,146)	0
Net cash (used in) provided by financing activities	(24,545)	67,027
Net (decrease) increase in cash and cash equivalents	(13,145)	2,207
Cash and cash equivalents at beginning of period	48,595	29,819
Cash and cash equivalents at end of period	$ 35,450	$ 32,026