Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Service cost, net	$ 5,191	$ 5,281	$ 10,597	$ 10,600
Interest cost on projected benefit obligations	2,169	1,409	4,405	2,810
Expected return on plan assets	(10,570)	(10,398)	(21,541)	(20,863)
Recognition of prior service cost	(1,064)	(484)	(2,178)	(974)
Recognition of actuarial losses/(gains)	5,286	6,966	10,793	13,985
Net periodic pension cost/(credit)	1,012	2,774	2,076	5,558
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost, net	416	374	832	748
Interest cost on projected benefit obligations	674	549	1,348	1,098
Expected return on plan assets	(1,547)	(1,494)	(3,094)	(2,988)
Recognition of prior service cost	0	0	0	0
Recognition of actuarial losses/(gains)	585	729	1,169	1,458
Net periodic pension cost/(credit)	128	158	255	316
Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost, net	4,775	4,907	9,765	9,852
Interest cost on projected benefit obligations	1,492	858	3,051	1,708
Expected return on plan assets	(9,023)	(8,904)	(18,447)	(17,875)
Recognition of prior service cost	(1,045)	(465)	(2,141)	(936)
Recognition of actuarial losses/(gains)	4,709	6,246	9,639	12,545
Net periodic pension cost/(credit)	908	2,642	1,867	5,294
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year, Description	28,200		28,200
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost, net	0	0	0	0
Interest cost on projected benefit obligations	3	2	6	4
Expected return on plan assets	0	0	0	0
Recognition of prior service cost	(19)	(19)	(37)	(38)
Recognition of actuarial losses/(gains)	(8)	(9)	(15)	(18)
Net periodic pension cost/(credit)	(24)	$ (26)	(46)	$ (52)
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year, Description	$ 100		$ 100