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Asset Retirement Obligations (Tables)
12 Months Ended
Dec. 31, 2019
Asset Retirement Obligations [Abstract]  
Summary of Changes in Asset Retirement Obligations

Year Ended December 31,

(in thousands)

2019

2018

2017

Beginning balance

$

14,816

$

20,163

$

18,612

Accretion

812

1,180

951

Additions

595

Acquisitions and dispositions

(103)

Revisions

(379)

(6,527)

703

Ending balance

$

15,844

$

14,816

$

20,163