Asset Retirement Obligations
12 Months Ended
Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]  
Asset Retirement Obligations
Note 5—Asset Retirement Obligations
The following table summarizes the period-to-period changes in the Company’s asset retirement obligations (“ARO”) that are associated with its oil and gas properties for the periods presented:
(in thousands)December 31, 2020December 31, 2019
Asset retirement obligations, beginning of period$16,874 $13,895 
Liabilities incurred589 1,393 
Liabilities on acquired properties147 1,167 
Liabilities divested and settled(578)(1,361)
Accretion expense1,128 912 
Revision to estimated cash flows(1,151)868 
Asset retirement obligations, end of period$17,009 $16,874 

ARO reflect the present value of the estimated future costs associated with the plugging and abandonment of oil and gas wells, removal of equipment and facilities from leased acreage and land restoration in accordance with applicable local, state and federal laws. Inherent in the present value calculation of ARO are numerous estimates and assumptions, including plug and abandonment settlement amounts, inflation factors, credit adjusted discount rates and the timing of ultimate ARO settlement. To the extent future revisions to these assumptions impact the value of the existing ARO liabilities, a corresponding offsetting adjustment is made to the oil and gas property balance. Changes in the liability due to the passage of time are recognized as an increase in the carrying amount of the liability with an offsetting charge to accretion expense, which is included within depreciation, depletion and amortization.