Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 6,771	$ 54,372	[1]
Accounts receivable, net	57,221	53,978	[1]
Accounts receivable affiliates	9,257	11,448	[1]
Fair value of derivatives	38,797	42,953	[1]
Prepaid expenses and other current assets	15,855	14,072	[1]
Total current assets	127,901	176,823	[1]
Properties and equipment, net	1,244,413	1,120,038	[1]
Assets held for sale	0	5,191	[1]
Fair value of derivatives	34,546	44,464	[1]
Accounts receivable affiliates	4,819	8,478	[1]
Other assets	32,006	34,041	[1]
Total Assets	1,443,685	1,389,035	[1]
Current liabilities:
Accounts payable	103,620	47,271	[1]
Accounts payable affiliates	8,084	9,605	[1]
Production tax liability	18,490	16,226	[1]
Fair value of derivatives	30,349	29,998	[1]
Funds held for distribution	30,755	29,755	[1]
Accrued interest payable	10,396	10,051	[1]
Other accrued expenses	21,408	17,723	[1]
Total current liabilities	223,102	160,629	[1]
Long-term debt	314,124	295,695	[1]
Deferred income taxes	179,711	187,999	[1]
Asset retirement obligations	28,414	27,797	[1]
Fair value of derivatives	32,230	36,644	[1]
Accounts payable affiliates	7,353	12,111	[1]
Other liabilities	21,360	25,919	[1]
Total liabilities	806,294	746,794	[1]
Commitments and contingent liabilities			[1]
Shareholders' Equity:
Preferred shares, par value $0.01 per share; authorized 50,000,000 shares; issued: none	0	0	[1]
Common shares, par value $0.01 per share, authorized 100,000,000 shares; issued: 23,565,040 in 2011 and 23,462,326 in 2010	236	235	[1]
Additional paid-in capital	215,237	209,198	[1]
Retained earnings	422,084	432,843	[1]
Treasury shares, at cost: 6,238 in 2011 and 2,938 in 2010	(242)	(111)	[1]
Total shareholders' equity	637,315	642,165	[1]
Noncontrolling interest in subsidiary	76	76	[1]
Total equity	637,391	642,241	[1]
Total Liabilities and Equity	$ 1,443,685	$ 1,389,035	[1]

[1] Derived from audited 2010 balance sheet.