v3.25.2
Pension and Postretirement Plans (Total Benefit/Cost) (Details 1) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Defined Benefit Plan Disclosure [Line Items]        
Net Periodic Cost (Benefit)     $ (40,985) $ (40,313)
Defined Benefit Pension Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Service cost $ 11,699 $ 14,071 23,891 28,105
Interest cost 6,956 11,246 13,377 22,440
Expected return on assets (41,881) (41,239) (83,852) (82,929)
Amortization of prior service credit (521) (482) (1,040) (976)
Recognized actuarial gain 0 (11,263) 0 (23,781)
Net Periodic Cost (Benefit) (23,747) (27,667) (47,624) (57,141)
Special separation benefit expense 6,015 16,410 6,639 16,828
Net Periodic Cost (Benefit) (17,732) (11,257) (40,985) (40,313)
Supplemental Executive Retirement Plan (SERP) [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Service cost 238 288 477 575
Interest cost 1,197 1,129 2,394 2,257
Net Periodic Cost (Benefit) 1,435 1,417 2,871 2,832
Other Postretirement Plans [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Interest cost 12 14 22 28
Recognized actuarial gain (380) (470) (759) (939)
Net Periodic Cost (Benefit) $ (368) $ (456) $ (737) $ (911)