ASSET RETIREMENT OBLIGATIONS (Tables)

9 Months Ended

Sep. 30, 2020

ASSET RETIREMENT OBLIGATIONS [Abstract]

Asset Retirement Obligations Operating Costs

	Three Months Ended		Nine Months Ended
	September 30		September 30
in thousands	2020	2019	2020	2019
ARO Operating Costs
Accretion	$        3,115	$        2,744	$        9,270	$        8,194
Depreciation	2,123	1,720	6,022	5,361
Total	$        5,238	$        4,464	$      15,292	$      13,555

Reconciliations of Asset Retirement Obligations

	Three Months Ended		Nine Months Ended
	September 30		September 30
in thousands	2020	2019	2020	2019
Asset Retirement Obligations
Balance at beginning of period	$     263,748	$     223,497	$     210,323	$     225,726
Liabilities incurred	353	0	353	263
Liabilities settled	(2,459)	(2,684)	(11,047)	(9,650)
Accretion expense	3,115	2,744	9,270	8,194
Revisions, net	(5,809)	510	50,049	(466)
Balance at end of period	$     258,948	$     224,067	$     258,948	$     224,067