Stockholder's Equity - Accumulated Other Comprehensive Income (Loss) (Tables)

6 Months Ended

Jun. 30, 2024

Equity [Abstract]

Changes in Accumulated Other Comprehensive Loss

	Defined Benefit		Commodity		Interest Rate
	Pension and		Contract		Swap
	Postretirement		Cash Flow		Cash Flow
	Plan Items		Hedges		Hedges		Total
(in thousands)
As of December 31, 2023	$	(2,584)	$	(274)	$	120	$	(2,738)
Other comprehensive income before reclassifications	—		1,640		511		2,151
Amounts reclassified from accumulated other comprehensive income (loss)	27		(761)		(255)		(989)
Net current-period other comprehensive income (loss)	27		879		256		1,162
As of June 30, 2024	$	(2,557)	$	605	$	376	$	(1,576)

As of December 31, 2022	$	(2,506)	$	1,092	$	35	$	(1,379)
Other comprehensive income (loss) before reclassifications	—		(2,045)		612		(1,433)
Amounts reclassified from accumulated other comprehensive income (loss)	21		(126)		(142)		(247)
Net prior-period other comprehensive income (loss)	21		(2,171)		470		(1,680)
As of June 30, 2023	$	(2,485)	$	(1,079)	$	505	$	(3,059)