XML 70 R55.htm IDEA: XBRL DOCUMENT v3.21.2
ASSET RETIREMENT OBLIGATIONS - SCHEDULE OF ROLL FORWARD ACTIVITY (Details)
$ in Thousands
9 Months Ended
Sep. 30, 2021
USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]  
Beginning balance as of December 31, 2020 $ 28,699
Liabilities settled (3,885)
Additions 24,658
Accretion expense 1,290
Ending balance as of September 30, 2021 $ 50,762