Components of Pension and Other Post-employment Benefit (OPEB) Plans Net Periodic Benefit Costs - Components of Net Periodic Benefit (Credit) Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pension Benefits
Defined Contribution Plan Disclosure [Line Items]
Service Cost	$ 302	$ 304
Interest Cost	6,431	6,757
Expected Return on Plan Assets	(7,991)	(9,867)
Amortization of Prior Service Credits	0	0
Amortization of Actuarial Loss (Gain)	1,566	185
Net Periodic Benefit Cost (Credit)	308	(2,621)
Other Post-Employment Benefits
Defined Contribution Plan Disclosure [Line Items]
Service Cost	0	0
Interest Cost	2,758	3,261
Expected Return on Plan Assets	0	0
Amortization of Prior Service Credits	(601)	(601)
Amortization of Actuarial Loss (Gain)	(70)	0
Net Periodic Benefit Cost (Credit)	$ 2,087	$ 2,660