Accumulated Other Comprehensive Earnings (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period			$ 769,042
Balance at the end of the period	$ 783,601	$ 756,762	783,601	$ 756,762
Foreign Currency Translation Adjustment
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	(24,419)	(24,388)	(24,882)	(24,581)
Other comprehensive earnings (loss) before reclassifications	120	(495)	583	(302)
Other comprehensive earnings (loss) net of tax	120	(495)	583	(302)
Balance at the end of the period	(24,299)	(24,883)	(24,299)	(24,883)
Investments
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	(7,575)	793	(1,286)	1,992
Other comprehensive earnings (loss) before reclassifications	(2,518)	(496)	(8,799)	(1,655)
Reclassifications from accumulated other comprehensive loss	(3)	(29)	(11)	(69)
Other comprehensive earnings (loss) net of tax	(2,521)	(525)	(8,810)	(1,724)
Balance at the end of the period	(10,096)	268	(10,096)	268
Foreign Currency Derivatives
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	124	543	322	589
Other comprehensive earnings (loss) before reclassifications	(365)	(82)	(421)	49
Reclassifications from accumulated other comprehensive loss	(37)	(81)	(179)	(258)
Other comprehensive earnings (loss) net of tax	(402)	(163)	(600)	(209)
Balance at the end of the period	(278)	380	(278)	380
Commodity Derivatives
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	76	572	94	713
Other comprehensive earnings (loss) before reclassifications	(45)	313	5	1,182
Reclassifications from accumulated other comprehensive loss	(55)	(618)	(123)	(1,628)
Other comprehensive earnings (loss) net of tax	(100)	(305)	(118)	(446)
Balance at the end of the period	(24)	267	(24)	267
Postretirement and Pension Benefits
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	426	939	739	1,472
Reclassifications from accumulated other comprehensive loss	(157)	(266)	(470)	(799)
Other comprehensive earnings (loss) net of tax	(157)	(266)	(470)	(799)
Balance at the end of the period	269	673	269	673
Accumulated Other Comprehensive Earnings (Loss).
Accumulated other comprehensive earnings (loss), net of tax
Balance at the beginning of the period	(31,368)	(21,541)	(25,013)	(19,815)
Other comprehensive earnings (loss) before reclassifications	(2,808)	(760)	(8,632)	(726)
Reclassifications from accumulated other comprehensive loss	(252)	(994)	(783)	(2,754)
Other comprehensive earnings (loss) net of tax	(3,060)	(1,754)	(9,415)	(3,480)
Balance at the end of the period	$ (34,428)	$ (23,295)	$ (34,428)	$ (23,295)