v3.26.1
Retirement Benefits - Activity (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2026
SERP Pension Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Employer contributions $ 2.0 $ 3.0  
Forecast | Qualified Pension Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Aggregate expected contributions     $ 18.0
Forecast | SERP Pension Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Aggregate expected contributions     3.4
Forecast | Other Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Aggregate expected contributions     $ 0.2