Pensions and Other Postretirement Benefits (Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Pension settlement charge		$ 0	$ 0	$ 0	$ 190
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost		2	2	4	4
Interest cost		26	24	52	55
Expected return on plan assets		(27)	(24)	(54)	(55)
Amortization of actuarial (gains) losses		5	3	11	10
Pension settlement charge	$ 190	8	1	8	191
Net periodic benefit cost		14	6	21	205
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost		1	1	2	2
Interest cost		6	6	12	13
Amortization of actuarial (gains) losses		(1)	(1)	(1)	(1)
Amortization of prior service credit		0	(1)	(2)	(3)
Net periodic benefit cost		$ 6	$ 5	$ 11	$ 11