CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 4,441	$ 6,252
Accounts receivable, net of allowance for doubtful accounts	104,636	189,627
Derivative assets	80,372	128,981
Deferred income taxes	0	53
Other current assets	8,381	10,114
Total current assets	197,830	335,027
Property and equipment, net (successful efforts method)	1,888,892	1,825,098
Derivative assets	19,546	35,897
Other assets	6,322	5,841
Total assets	2,112,590	2,201,863
Current liabilities
Accounts payable and accrued liabilities	197,889	312,227
Derivative liabilities	0	0
Total current liabilities	197,889	312,227
Other liabilities	117,582	123,886
Deferred income taxes	4,838	4,504
Long-term debt, net of unamortized issuance costs	$ 1,264,363	$ 1,085,429
Commitments and contingencies (Note 12)
Shareholders’ equity:
Preferred stock of $100 par value – 100,000 shares authorized; Series A – 7,945 shares issued as of June 30, 2015 and December 31, 2014 and Series B – 32,500 shares issued as of June 30, 2015 and December 31, 2014, each with a redemption value of $10,000 per share	$ 4,044	$ 4,044
Common stock of $0.01 par value – 228,000,000 shares authorized; 71,676,606 and 71,568,936 shares issued as of June 30, 2015 and December 31, 2014, respectively	530	529
Paid-in capital	1,207,854	1,206,305
Accumulated deficit	(684,604)	(535,176)
Deferred compensation obligation	3,354	3,211
Accumulated other comprehensive income	228	249
Treasury stock – 293,426 and 262,070 shares of common stock, at cost, as of June 30, 2015 and December 31, 2014, respectively	(3,488)	(3,345)
Total shareholders’ equity	527,918	675,817
Total liabilities and shareholders’ equity	$ 2,112,590	$ 2,201,863