v3.25.2
Retirement Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Employees' Pension Plan        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost $ 402 $ 380 $ 802 $ 846
Interest Cost 577 595 1,161 1,120
Expected Return on Plan Assets (977) (923) (1,986) (1,855)
Amortization of Prior Service Cost 48 33 95 66
Amortization of Net Loss (Gain) 0 0 0 0
Net Periodic Benefit Cost (Benefit) 50 85 72 177
Plan Contributions During the Period 0 0 0 0
Estimated Future Contributions in the Current Fiscal Year 0   0  
Select Executive Retirement Plan        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost 21 22 47 39
Interest Cost 76 2 148 160
Expected Return on Plan Assets 0 0 0 0
Amortization of Prior Service Cost 10 10 20 20
Amortization of Net Loss (Gain) 0 (9) 0 12
Net Periodic Benefit Cost (Benefit) 107 25 215 231
Plan Contributions During the Period 128 128 248 255
Estimated Future Contributions in the Current Fiscal Year 248   248  
Postretirement Benefit Plans        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost 5 8 16 23
Interest Cost 60 79 139 160
Expected Return on Plan Assets 0 0 0 0
Amortization of Prior Service Cost 25 25 51 51
Amortization of Net Loss (Gain) (159) (82) (255) (169)
Net Periodic Benefit Cost (Benefit) (69) 30 (49) 65
Plan Contributions During the Period 34 $ 54 91 $ 81
Estimated Future Contributions in the Current Fiscal Year $ 91   $ 91