Annual report pursuant to Section 13 and 15(d)

Asset Retirement Obligations (Details)

v3.22.4
Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Asset Retirement Obligations      
Beginning of period $ 29,915 $ 29,965 $ 30,972
Change in estimated reclamation costs 326 (536) (1,583)
Accretion expense 460 486 576
End of period $ 30,701 $ 29,915 $ 29,965