Employee Benefit Plans, Pre-Tax Amounts in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Pension Plans [Member]
Pension and Other Postretirement Benefit Plans Accumulated Other Comprehensive Loss, before Tax
Net actuarial (gain) loss	$ (115)	$ 62
Prior service cost	20	22
Total	(95)	84
Other Postretirement Benefit Plans [Member]
Pension and Other Postretirement Benefit Plans Accumulated Other Comprehensive Loss, before Tax
Net actuarial (gain) loss	(87)	(96)
Prior service cost	1	1
Total	$ (86)	$ (95)