Pensions and Other Postretirement Benefit Plans (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Pension plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,473	$ 986
Interest cost	4,545	3,447
Expected return on assets	(4,030)	(3,063)
Amortization of prior service cost/(income)	(20)	(24)
Amortization of net actuarial loss	556	421
Net periodic benefit cost/(credit)	2,524	1,767
Other postretirement benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	35	45
Interest cost	1,063	1,405
Expected return on assets	0	0
Amortization of prior service cost/(income)	(93)	(3,068)
Amortization of net actuarial loss	(26)	621
Net periodic benefit cost/(credit)	$ 979	$ (997)