Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2019

Asset Retirement Obligation [Abstract]

Schedule of reconciliation of the ARO

	December 31,
(in thousands)	2019			2018
Balance at beginning of year	$	22,310		$	7,357
Accretion expense		1,625			868
Additions and revisions		294			-
Obligations discharged with divestitures		(1,694	)		-
Change in estimate of cash outflow		-			361
Additions from Carbon California (Note 3)		-			2,921
Additions from Seneca Acquisition (Note 3)		-			5,132
Additions from Liberty Acquisition (Note 3)		-			45
Additions from OIE Membership Acquisition		-			5,626
Balance at end of year	$	22,535		$	22,310
Less: Current portion		(5,021	)		(3,099	)
Non-current portion	$	17,514		$	19,211