Pension and Postretirement Plans (Total Benefit/Cost) (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 14,034	$ 9,243
Net Periodic Cost (Benefit)	(29,056)	(23,162)
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	14,034	9,243
Interest cost	11,194	11,534
Expected return on assets	(41,690)	(38,338)
Amortization of prior service cost (credit)	(494)	410
Recognized actuarial loss (gain)	(12,518)	(10,140)
Net Periodic Cost (Benefit)	(29,474)	(27,291)
Special separation benefit expense	418	4,129
Net Periodic Cost (Benefit)	(29,056)	(23,162)
Supplemental Executive Retirement Plan (SERP) [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	287	148
Interest cost	1,128	1,165
Net Periodic Cost (Benefit)	1,415	1,313
Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	14	22
Amortization of prior service cost (credit)	0	(1)
Recognized actuarial loss (gain)	(469)	(626)
Net Periodic Cost (Benefit)	$ (455)	$ (605)