Consolidated balance sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 399,506	$ 198,153
Accounts receivable, net	95,720	77,318
Derivatives	1,360	15,806
Deferred income taxes	13,588	3,634
Other current assets	20,447	12,698
Total current assets	530,621	307,609
Oil and natural gas properties, full cost method:
Proved properties	3,698,051	3,276,578
Unproved properties not being amortized	225,056	208,085
Midstream service assets	80,265	51,704
Other fixed assets	42,016	32,832
Total property and equipment	4,045,388	3,569,199
Less accumulated depletion, depreciation, amortization and impairment	(1,467,172)	(1,364,875)
Net property and equipment	2,578,216	2,204,324
Derivatives	0	79,726
Deferred loan costs, net	31,088	25,933
Investment in equity method investee	40,871	5,913
Other assets, net	242	255
Total assets	3,181,038	2,623,760
Current liabilities:
Accounts payable	18,387	16,002
Accrued payable - affiliates	20,104	3,489
Undistributed revenue and royalties	44,122	35,124
Accrued capital expenditures	129,674	116,328
Derivatives	44,374	10,795
Other current liabilities	78,007	72,231
Total current liabilities	334,668	253,969
Long-term debt	1,501,419	1,051,538
Derivatives	36,317	2,680
Deferred income taxes	15,980	16,293
Asset retirement obligations	22,975	21,478
Other noncurrent liabilities	5,370	5,546
Total liabilities	1,916,729	1,351,504
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, 50,000,000 shares authorized and zero issued at June 30, 2014 and December 31, 2013	0	0
Common stock, $0.01 par value, 450,000,000 shares authorized, and 143,737,390 and 142,671,436 issued, at June 30, 2014 and December 31, 2013, respectively	1,437	1,427
Additional paid-in capital	1,294,964	1,283,809
Accumulated deficit	(32,092)	(12,980)
Total stockholders’ equity	1,264,309	1,272,256
Total liabilities and stockholders’ equity	$ 3,181,038	$ 2,623,760