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		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pension Benefits
Defined Contribution Plan Disclosure [Line Items]
Service Cost	$ 302	$ 305	$ 604	$ 609
Interest Cost	6,431	6,757	12,862	13,514
Expected Return on Plan Assets	(7,991)	(9,868)	(15,982)	(19,735)
Amortization of Prior Service Credits	0	0	0	0
Amortization of Actuarial Loss (Gain)	1,566	185	3,132	370
Net Periodic Benefit Cost (Credit)	308	(2,621)	616	(5,242)
Other Post-Employment Benefits
Defined Contribution Plan Disclosure [Line Items]
Service Cost	0	0	0	0
Interest Cost	2,758	3,261	5,516	6,522
Expected Return on Plan Assets	0	0	0	0
Amortization of Prior Service Credits	(602)	(602)	(1,203)	(1,203)
Amortization of Actuarial Loss (Gain)	(69)	0	(139)	0
Net Periodic Benefit Cost (Credit)	$ 2,087	$ 2,659	$ 4,174	$ 5,319