Retirement Benefits and Trusteed Assets (Target Allocations for Other Postretirement Benefit Plan Assets) (Details) - Other postretirement benefit plan	Dec. 31, 2025
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	100.00%
U.S. Large Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	4.00%
Non-U.S. Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	3.00%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	62.00%
Hedge Funds and Similar Investments
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	9.00%
Private Equity and Other
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets	22.00%