Accumulated Other Comprehensive Income (Loss) (Reclassifications out of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	$ 462	$ 1,771	$ 1,412	$ 5,920
Amortization of actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification	321	1,453	985	4,653
Prior service costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification	151	134	455	429
Pension and other post-retirement effects
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax expense (benefit)	20	213	62	925
Net of tax	492	1,800	1,502	6,007
Cash flow hedging activity
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification	(37)	(29)	(111)	(87)
Tax expense (benefit)	7	0	21	0
Net of tax	$ (30)	$ (29)	$ (90)	$ (87)