Pension and Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024	Apr. 01, 2024
Benefit Plan Information
Discontinued operation, pension plan benefit obligation				$ 2,700
Discontinued operation, postretirement plan benefit obligation				$ 2,400
Settlements, curtailments, special termination benefits and other			$ 800
U.S. Pension Plans
Benefit Plan Information
Company contributions		$ 89
U.S. Pension Plans | United States
Benefit Plan Information
Decrease in accumulated comprehensive loss	$ 110
Pension payment obligations transferred			$ 2,500
Postretirement benefits
Benefit Plan Information
Company contributions		$ 10