Oil And Gas Properties (Tables)

3 Months Ended

Mar. 31, 2012

Oil And Gas Properties [Abstract]

Components Of Exploration Expenses

		Three Months Ended
		March 31,
		2012			2011
		(in thousands)
Delay rental and geological and geophysical costs	$	611		$	355
Impairment of unproved properties........................		144			–
Dry hole expense.................................................		(1	)		(9	)
Total exploration expense................................	$	754		$	346

Changes In Asset Retirement Obligations

Asset retirement obligations at December 31, 2011 ............	$	254,391
Liability incurred during the period......................................		115
Liability settled during the period........................................		(34,665	)
Other revisions in estimated cash flows..............................		5,755
Accretion expense (included in depreciation and amortization)		3,439
Asset retirement obligations at March 31, 2012...................	$	229,035