Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2017

Asset Retirement Obligation Disclosure [Abstract]

Schedule of Asset Retirement Obligations

The following table summarizes the changes in the Company’s asset retirement obligations (“AROs”) for the six months ended June 30, 2017:

(in thousands)	Six Months Ended June 30, 2017
Asset retirement obligations, beginning of period	$	7,226
Additional liabilities incurred	1,443
Liabilities settled	(29		)
Accretion expense	233
Revision to estimated cash flows	(18		)
Asset retirement obligations, end of period	$	8,855