Consolidated Balance Sheets (Unaudited) (USD $) In Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
ASSETS
Cash and Cash Equivalents	$ 3,556	$ 1,732
Accounts Receivable:
Oil and gas sales	40,206	28,705
Joint interest operations	11,112	15,982
Marketable Securities	62,482	84,637
Other Current Assets	13,129	4,675
Total current assets	130,485	135,731
Property and Equipment:
Unevaluated oil and gas properties	196,753	225,884
Oil and gas properties, successful efforts method	2,943,581	2,574,717
Other	18,028	18,156
Accumulated depreciation, depletion and amortization	(1,137,075)	(1,002,509)
Net property and equipment	2,021,287	1,816,248
Other Assets	16,677	12,235
Total Assets	2,168,449	1,964,214
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts Payable	134,159	123,275
Deferred Income Taxes Payable	11,427	10,339
Accrued Expenses	26,438	21,450
Total current liabilities	172,024	155,064
Long-term Debt	691,640	513,372
Deferred Income Taxes Payable	217,992	217,993
Reserve for Future Abandonment Costs	7,009	6,674
Other Non-Current Liabilities	2,499	2,580
Total liabilities	1,091,164	895,683
Commitments and Contingencies
Stockholders' Equity:
Common stock - $0.50 par, 75,000,000 shares authorized, 47,647,176 and 47,706,101 shares outstanding at June 30, 2011 and December 31, 2010, respectively	23,824	23,853
Additional paid-in capital	460,928	454,499
Retained earnings	564,202	557,849
Accumulated other comprehensive income	28,331	32,330
Total stockholders' equity	1,077,285	1,068,531
Total liabilities and stockholders' equity	$ 2,168,449	$ 1,964,214