CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 123,690	$ 23,474
Accounts receivable, net of allowance for doubtful accounts	188,683	194,403
Derivative assets	13,680	3,830
Deferred Tax Assets, Net of Valuation Allowance, Current	6,040	6,065
Other current assets	6,951	5,924
Total current assets	339,044	233,696
Property and equipment, net (successful efforts method)	2,342,903	2,237,304
Derivative assets	8,572	1,552
Other assets	31,860	34,535
Total assets	2,722,379	2,507,087
Current liabilities
Accounts payable and accrued liabilities	276,593	248,004
Derivative liabilities	1,045	10,141
Total current liabilities	277,638	258,145
Other liabilities	125,646	33,386
Derivative liabilities	0	0
Deferred income taxes	145,428	145,752
Long-term debt	1,075,000	1,281,000
Commitments and contingencies (Note 11)
Shareholders’ equity:
Preferred stock of $100 par value – 100,000 shares authorized; Series A – 7,945 and 11,500 shares issued as of September 30, 2014 and December 31, 2013 and Series B – 32,500 shares issued as of September 30, 2014, each with a redemption value of $10,000 per share	4,044	1,150
Common stock of $0.01 par value – 128,000,000 shares authorized; 71,557,951 and 65,306,748 shares issued as of September 30, 2014 and December 31, 2013, respectively	528	466
Paid-in capital	1,205,302	891,351
Accumulated deficit	(111,415)	(104,180)
Deferred compensation obligation	3,106	2,792
Accumulated other comprehensive income	341	267
Treasury stock – 246,352 and 233,063 shares of common stock, at cost, as of September 30, 2014 and December 31, 2013, respectively	(3,239)	(3,042)
Total shareholders’ equity	1,098,667	788,804
Total liabilities and shareholders’ equity	$ 2,722,379	$ 2,507,087