Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Current Assets:
Cash and cash equivalents	$ 3,277		$ 170
Accounts receivable	70,897		67,318
Deferred tax asset	4,974		5,679
Other current assets	7,600		7,370
Total Current Assets	86,748		80,537
Property and Equipment:
Property and Equipment, including $71,452 and $92,579 of unproved property costs not being amortized, respectively	5,714,099		5,192,793
Less - Accumulated depreciation, depletion, and amortization	(3,174,453)		(2,847,773)
Property and Equipment, Net	2,539,646		2,345,020
Other Long-Term Assets	17,199		18,504
Total Assets	2,643,593		2,444,061
Current Liabilities:
Accounts payable and accrued liabilities	83,361		75,378
Accrued capital costs	61,164		73,190
Accrued interest	21,561		21,362
Undistributed oil and gas revenues	10,990		7,550
Total Current Liabilities	177,076		177,480
Long-Term Debt	1,142,368	[1]	916,934	[1]
Deferred Tax Liabilities	217,384		223,243
Asset Retirement Obligation	63,225		79,643
Other Long-Term Liabilities	10,324		9,901
Commitments and Contingencies	0		0
Stockholders' Equity:
Preferred stock, $.01 par value, 5,000,000 shares authorized, none outstanding	0		0
Common stock, $.01 par value, 150,000,000 shares authorized, 43,915,346 and 43,450,367 shares issued, and 43,401,920 and 42,930,071 shares outstanding, respectively	439		435
Additional paid-in capital	761,972		747,868
Treasury stock held, at cost, 513,426 and 520,296 shares, respectively	(12,575)		(13,855)
Retained earnings	283,380		302,412
Total Stockholders' Equity	1,033,216		1,036,860
Total Liabilities and Stockholders' Equity	$ 2,643,593		$ 2,444,061

[1] Amounts are shown net of any debt discount or premium