Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2023

Asset Retirement Obligation Disclosure [Abstract]

Summary of Changes in Asset Retirement Obligation Liability Balances

The components of the changes in the asset retirement obligation liabilities for the periods stated were as follows:

(Dollars in thousands)	Short-Term Portion		Long-Term Portion		Total
Balance as of December 31, 2021	$	130	$	6,355	$	6,485
Accretion	138		542		680
Amounts paid	(288)		—		(288)
Additions	70		533		603
Reclassifications	193		(193)		—
Balance as of December 31, 2022	243		7,237		7,480
Accretion	(4)		660		656
Amounts paid	(243)		—		(243)
Additions	(33)		(463)		(496)
Reclassifications	243		(243)		—
Balance as of December 31, 2023	$	206	$	7,191	$	7,397