Benefit Plans (Projected Benefit Obligations, Plan Assets and Funded Status of Pension Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Change in plan assets:
Accrued pension costs	$ (122)	$ (136)
Accrued postretirement health care costs	(939)	(935)
Pension [Member]
Change in benefit obligation:
Benefit obligation at beginning of year (1)	6,082	6,428
Service cost	37	41	$ 39
Interest cost	318	321	333
Benefits paid	(457)	(457)
Actuarial (gains) losses	216	(251)
Plan amendments	4	0
Benefit obligation at end of year (1)	6,200	6,082	6,428
Change in plan assets:
Fair value of plan assets at beginning of year	6,545	6,775
Actual return on plan assets	646	209
Employer contributions	16	18
Benefits paid	(457)	(457)
Fair value of plan assets at end of year	6,750	6,545	6,775
Funded status at December 31	550	463
Other assets	727	624
Other accrued liabilities	(55)	(25)
Accrued pension costs	(122)	(136)
Accrued postretirement health care costs	0	0
Defined benefit plan, amounts for asset (liability) recognized in statement of financial position	550	463
Postretirement Benefit Plan [Member]
Change in benefit obligation:
Benefit obligation at beginning of year (1)	1,078	1,246
Service cost	11	15	15
Interest cost	56	62	65
Benefits paid	(90)	(91)
Actuarial (gains) losses	21	(153)
Plan amendments	0	(1)
Benefit obligation at end of year (1)	1,076	1,078	1,246
Change in plan assets:
Fair value of plan assets at beginning of year	84	102
Actual return on plan assets	9	12
Employer contributions	0	0
Benefits paid	(23)	(30)
Fair value of plan assets at end of year	70	84	$ 102
Funded status at December 31	(1,006)	(994)
Other assets	0	0
Other accrued liabilities	(67)	(59)
Accrued pension costs	0	0
Accrued postretirement health care costs	(939)	(935)
Defined benefit plan, amounts for asset (liability) recognized in statement of financial position	$ (1,006)	$ (994)