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Retirement Benefits Plan Assumptions (Details 5)
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Benefit Obligation [Member]        
Defined Benefit Plan Disclosure (Table Amounts)        
Initial health care cost trend rate assumed for the next year   5.30% 5.60% 5.90%
Rate to which the health care cost trend rate is assumed to decline (the ultimate trend rate)   5.00% 5.00% 5.00%
Year that the health care cost trend rate reaches the ultimate trend rate   2023 2023 2023
Pension Benefits        
Assumptions Used to Determine Benefit Obligation        
Discount rate   2.98% 2.68% 3.39%
Initial cash balance crediting rate assumed for the next year   2.25% 2.25% 2.39%
Rate to which the cash balance crediting rate is assumed to increase (the ultimate rate)   2.25% 2.25% 2.64%
Year that the cash balance crediting rate reaches the ultimate rate   2027 2026 2025
Rate of compensation increase   3.00% 3.00% 3.00%
Assumptions Used to Determine Benefit Cost        
Discount rate   2.68% 3.39%  
Initial cash balance crediting rate assumed for the next year   2.25% 2.39%  
Rate to which the cash balance crediting rate is assumed to increase (the ultimate rate)   2.25% 2.64%  
Year that the cash balance crediting rate reaches the ultimate rate   2026 2025  
Expected long-term return on plan assets   7.50% 8.00%  
Rate of compensation increase   3.00% 3.00%  
Pension Benefits | Subsequent Event [Member]        
Assumptions Used to Determine Benefit Cost        
Discount rate 2.98%      
Initial cash balance crediting rate assumed for the next year 2.25%      
Rate to which the cash balance crediting rate is assumed to increase (the ultimate rate) 2.25%      
Year that the cash balance crediting rate reaches the ultimate rate 2027      
Expected long-term return on plan assets 7.50%      
Rate of compensation increase 3.00%      
Post-retirement Benefit Cost [Member]        
Defined Benefit Plan Disclosure (Table Amounts)        
Initial health care cost trend rate assumed for the next year   5.60% 5.90%  
Rate to which the health care cost trend rate is assumed to decline (the ultimate trend rate)   5.00% 5.00%  
Year that the health care cost trend rate reaches the ultimate trend rate   2023 2023  
Post-retirement Benefit Cost [Member] | Subsequent Event [Member]        
Defined Benefit Plan Disclosure (Table Amounts)        
Initial health care cost trend rate assumed for the next year 5.30%      
Rate to which the health care cost trend rate is assumed to decline (the ultimate trend rate) 5.00%      
Year that the health care cost trend rate reaches the ultimate trend rate 2023      
Medical and Life Benefits        
Assumptions Used to Determine Benefit Obligation        
Discount rate   2.93% 2.58% 3.35%
Assumptions Used to Determine Benefit Cost        
Discount rate   2.58% 3.35%  
Expected long-term return on plan assets   7.22% 7.66%  
Medical and Life Benefits | Subsequent Event [Member]        
Assumptions Used to Determine Benefit Cost        
Discount rate 2.93%      
Expected long-term return on plan assets 7.19%