Employee Benefit Plans - Components of Net Periodic Benefit Cost (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 1
Interest cost	(44)	(45)
Expected return on plan assets	(57)	(59)
Amortization of prior service credit	0	0
Amortization of actuarial loss	(8)	(7)
Net periodic cost (benefit)	(5)	(6)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	(2)	(2)
Expected return on plan assets	0	0
Amortization of prior service credit	(2)	(2)
Amortization of actuarial loss	(1)	(1)
Net periodic cost (benefit)	$ 1	$ 1