Pensions and Other Post-retirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3,099	$ 3,264	$ 9,297	$ 9,748
Interest cost	3,613	2,941	10,839	8,575
Expected return on plan assets	(12,418)	(9,532)	(37,254)	(27,826)
Amortization of prior service cost (credit)	36	66	108	198
Recognized net actuarial losses	3,018	4,421	9,054	13,263
Settlements			0	(1,879)
Net periodic benefit (income) cost	(2,652)	1,160	(7,956)	2,079
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	82	99	246	297
Interest cost	148	121	444	353
Expected return on plan assets	0	0	0	0
Amortization of prior service cost (credit)	(84)	(90)	(252)	(270)
Recognized net actuarial losses	310	399	930	1,197
Settlements			0	0
Net periodic benefit (income) cost	$ 456	$ 529	$ 1,368	$ 1,577