Asset Retirement Obligations (Tables)

3 Months Ended

Mar. 31, 2015

Asset Retirement Obligation Disclosure [Abstract]

Activity Related to Asset Retirement Obligations

Activity related to the Company’s asset retirement obligations is as follows:

(In thousands)	Three Months Ended   March 31, 2015
Balance at beginning of period	$	126,655
Liabilities incurred	4,355
Liabilities settled	(113		)
Accretion expense	1,644
Balance at end of period	$	132,541