CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 25,095	$ 23,474
Accounts receivable, net of allowance for doubtful accounts	238,325	194,403
Derivative assets	0	3,830
Deferred Tax Assets, Net of Valuation Allowance, Current	6,065	6,065
Assets Held-for-sale, Long Lived	71,957	0
Other current assets	5,631	5,924
Total current assets	347,073	233,696
Property and equipment, net (successful efforts method)	2,207,754	2,237,304
Derivative assets	0	1,552
Other assets	32,853	34,535
Total assets	2,587,680	2,507,087
Current liabilities
Accounts payable and accrued liabilities	240,254	248,004
Derivative liabilities	44,298	10,141
Total current liabilities	284,552	258,145
Other liabilities	44,901	33,386
Derivative liabilities	8,508	0
Deferred income taxes	103,327	145,752
Long-term debt	1,130,000	1,281,000
Commitments and contingencies (Note 11)
Shareholders’ equity:
Preferred stock of $100 par value – 100,000 shares authorized; Series A - 8,880 and 11,500 shares issued as of June 30, 2014 and December 31, 2013 and Series B - 32,500 shares issued as of June 30, 2014, each with a redemption value of $10,000 per share	4,138	1,150
Common stock of $0.01 par value – 128,000,000 shares authorized; 69,922,551 and 65,306,748 shares issued as of June 30, 2014 and December 31, 2013, respectively	512	466
Paid-in capital	1,204,224	891,351
Accumulated deficit	(192,547)	(104,180)
Deferred compensation obligation	3,001	2,792
Accumulated other comprehensive income	316	267
Treasury stock – 245,256 and 233,063 shares of common stock, at cost, as of June 30, 2014 and December 31, 2013, respectively	(3,252)	(3,042)
Total shareholders’ equity	1,016,392	788,804
Total liabilities and shareholders’ equity	$ 2,587,680	$ 2,507,087