v3.26.1
Employee Benefit Plans - PAC (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Other Postretirement Plans    
Defined Benefit Plan Disclosure [Line Items]    
Service cost $ 1 $ 1
Interest cost 7 7
Expected return on plan assets (10) (9)
Net amortization (1) (1)
Net periodic benefit (credit) cost (3) (2)
United States | Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service cost 3 3
Interest cost 25 26
Expected return on plan assets (31) (30)
Net amortization 2 2
Net periodic benefit (credit) cost (1) 1
PAC | Other Postretirement Plans    
Defined Benefit Plan Disclosure [Line Items]    
Service cost 0 0
Interest cost 3 3
Expected return on plan assets (3) (3)
Net amortization (1) (1)
Net periodic benefit (credit) cost (1) (1)
PAC | United States | Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Interest cost 9 9
Expected return on plan assets (11) (11)
Net amortization 2 2
Net periodic benefit (credit) cost $ 0 $ 0