Asset Retirement Obligations (Tables)

9 Months Ended

Sep. 30, 2013

Asset Retirement Obligation Disclosure [Abstract]

Schedule of changes in Company's asset retirement obligations

The following table summarizes the changes in the Company’s asset retirement obligations for the nine months ended September 30, 2013 (in thousands).

Beginning asset retirement obligations	$	5,769
Liabilities incurred during period	417
Liabilities settled during period	(57		)
Revisions in estimated cash flows	533
Accretion expense	248
Ending asset retirement obligations	6,910
Less: current asset retirement obligations(1)	(763		)
Long-term asset retirement obligations	$	6,147