ASSET RETIREMENT OBLIGATIONS (Tables)

3 Months Ended

Mar. 31, 2021

ASSET RETIREMENT OBLIGATIONS [Abstract]

Asset Retirement Obligations Operating Costs

	Three Months Ended
	March 31
in thousands	2021	2020
ARO Operating Costs
Accretion	$        3,196	$        2,908
Depreciation	2,661	1,836
Total	$        5,857	$        4,744

Reconciliations of Asset Retirement Obligations

	Three Months Ended
	March 31
in thousands	2021	2020
Asset Retirement Obligations
Balance at beginning of year	$     283,163	$     210,323
Liabilities incurred	938	0
Liabilities settled	(2,693)	(5,234)
Accretion expense	3,196	2,908
Revisions, net	797	55,448
Balance at end of period	$     285,401	$     263,445