ASSET RETIREMENT OBLIGATIONS (Tables)

6 Months Ended

Jun. 30, 2019

ASSET RETIREMENT OBLIGATIONS [Abstract]

Asset Retirement Obligations Operating Costs

	Three Months Ended		Six Months Ended
	June 30		June 30
in thousands	2019	2018	2019	2018
ARO Operating Costs
Accretion	$        2,717	$        2,668	$        5,450	$        5,352
Depreciation	1,800	1,343	3,641	2,680
Total	$        4,517	$        4,011	$        9,091	$        8,032

Reconciliations of Asset Retirement Obligations

	Three Months Ended		Six Months Ended
	June 30		June 30
in thousands	2019	2018	2019	2018
Asset Retirement Obligations
Balance at beginning of period	$     225,186	$     214,709	$     225,726	$     218,117
Liabilities incurred	263	0	263	0
Liabilities settled	(3,388)	(1,805)	(6,966)	(7,826)
Accretion expense	2,717	2,668	5,450	5,352
Revisions, net	(1,281)	(151)	(976)	(222)
Balance at end of period	$     223,497	$     215,421	$     223,497	$     215,421