Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Assets
Cash and cash equivalents	$ 224,743	$ 65,678
Restricted cash	15,040	20,113
Accounts receivable (net of allowance of $0 and $225, respectively)	85,430	70,628
Deferred tax asset	2,655	480
Derivative asset		2,194
Other current assets	18,222	28,050
Total current assets	346,090	187,143
Oil and gas properties (using the successful efforts method of accounting):
Proved properties	5,049,543	4,875,232
Unproved properties	24,691	22,945
Total oil and gas	5,074,234	4,898,177
Less accumulated depletion, depreciation, impairment and amortization	(1,853,185)	(1,760,756)
Oil and gas properties, net	3,221,049	3,137,421
Restricted cash	10,000	10,000
Deferred financing costs, net	37,874	40,873
Other assets, net	23,386	13,337
Total assets	3,638,399	3,388,774
Liabilities and Equity
Accounts payable and accruals	295,604	265,620
Current maturities of long-term debt	36,630	33,848
Asset retirement obligation	53,047	52,536
Deferred tax liability		138
Derivative liability	117,483	68,816
Current maturities of other long-term obligations	111,246	113,657
Total current liabilities	614,010	534,615
Long-term debt	2,115,483	1,976,157
Other long-term obligations	594,427	451,797
Asset retirement obligation	119,059	115,981
Deferred tax liability	41,737	27,493
Derivative liability	1,122	522
Total liabilities	3,485,838	3,106,565
Commitments and contingencies (Note 13)
Temporary equity:
Redeemable noncontrolling interest	115,819	115,820
8% convertible perpetual preferred stock: $0.001 par value; 790,957 shares and 806,847 shares issued and outstanding and liquidation value of $79.1 million and $80.7 million at March 31, 2012 and December 31, 2011, respectively	71,186	70,055
Shareholders' equity:
8% convertible perpetual preferred stock: $0.001 par value, 10,000,000 shares authorized; 2,314,043 shares and 2,318,153 shares issued and outstanding and liquidation value of $231.4 million and $231.8 million at March 31, 2012 and December 31, 2011, respectively.	219,550	222,681
Common stock: $0.001 par value, 100,000,000 shares authorized; 52,127,262 issued and 52,051,422 outstanding at March 31, 2012; 52,034,547 issued and 51,958,707 outstanding at December 31, 2011	52	52
Additional paid-in capital	527,103	529,669
Accumulated deficit	(687,665)	(548,765)
Accumulated other comprehensive loss	(92,573)	(106,392)
Treasury stock, at cost	(911)	(911)
Total shareholders' equity (deficit)	(34,444)	96,334
Total liabilities and equity	$ 3,638,399	$ 3,388,774