Asset Retirement Obligations

12 Months Ended

Dec. 31, 2020

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligations

(9) Asset Retirement Obligations

Our asset retirement obligations (“ARO”) primarily represent the present value of the estimated amounts we will incur to plug, abandon and remediate our producing properties at the end of their productive lives. Significant inputs used in determining such obligations include estimates of plugging and abandonment costs, estimated future inflation rates and well lives. The inputs are calculated based on historical data as well as current estimated costs. The following is a reconciliation of our liability for plugging and abandonment costs as of December 31, 2020 and 2019 (in thousands):

	2020			2019
Beginning of period	$	251,076		$	312,754
Liabilities incurred		1,483			4,063
Acquisitions		123			—
Liabilities settled		(4,634	)		(5,953	)
Disposition of wells		(176,748	)		(82,576	)
Accretion expense		7,518			15,658
Change in estimate		1,004			7,130
End of period		79,822			251,076
Less current portion		(6,689	)		(2,393	)
Long-term asset retirement obligations	$	73,133		$	248,683

Accretion expense is recognized as an increase to depreciation, depletion and amortization expense in the accompanying consolidated statements of operations.