Reclamation (Tables)

12 Months Ended

Dec. 31, 2020

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligation

Changes to the Company’s asset retirement obligations for its operating sites are as follows:

	Year Ended December 31,
In thousands	2020		2019
Asset retirement obligation - Beginning	$	134,398	$	133,508
Accretion	11,574		11,968
Additions and changes in estimates	(6,132)		(7,538)
Settlements	(2,720)		(3,540)
Asset retirement obligation - Ending	$	137,120	$	134,398