Pensions and Other Post-retirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,884	$ 3,099
Interest cost	5,918	3,613
Expected return on plan assets	(9,906)	(12,418)
Amortization of prior service cost (credit)	37	36
Recognized net actuarial losses	47	3,018
Net periodic benefit (income) cost	(2,020)	(2,652)
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	53	82
Interest cost	273	148
Expected return on plan assets	0	0
Amortization of prior service cost (credit)	(61)	(84)
Recognized net actuarial losses	138	310
Net periodic benefit (income) cost	$ 403	$ 456