Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2011

Notes To Financial Statements [Abstract]

Asset Retirement Obligations Reconciliation

The following presents a reconciliation of the asset retirement obligations (in thousands):

Asset retirement obligations at December 31, 2010	$	42,945
Liabilities added from acquisitions		6,966
Liabilities added from drilling		630
Current year accretion expense		1,817
Settlements		(1,028	)
Revision of estimate		784
Asset retirement obligations at June 30, 2011	$	52,114