Benefit Plans (Projected Benefit Obligations, Plan Assets and Funded Status of Pension Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Change in plan assets:
Accrued pension costs	$ (136)	$ (130)
Accrued postretirement health care costs	(935)	(1,079)
Pension [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	6,428	6,292
Service cost	41	39	$ 64
Interest cost	321	333	206
Benefits paid	(457)	(460)
Actuarial (gains) losses	(251)	224
Plan amendments	0	0
Benefit obligation at end of year	6,082	6,428	6,292
Change in plan assets:
Fair value of plan assets at beginning of year	6,775	6,603
Actual return on plan assets	209	612
Employer contributions	18	20
Benefits paid	(457)	(460)
Fair value of plan assets at end of year	6,545	6,775	6,603
Funded status at December 31	463	347
Other assets	624	506
Other accrued liabilities	(25)	(29)
Accrued pension costs	(136)	(130)
Accrued postretirement health care costs	0	0
Defined benefit plan, amounts for asset (liability) recognized in statement of financial position	463	347
Postretirement Benefit Plan [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	1,246	1,275
Service cost	15	15	23
Interest cost	62	65	41
Benefits paid	(91)	(96)
Actuarial (gains) losses	(153)	(10)
Plan amendments	(1)	(3)
Benefit obligation at end of year	1,078	1,246	1,275
Change in plan assets:
Fair value of plan assets at beginning of year	102	122
Actual return on plan assets	12	13
Employer contributions	0	0
Benefits paid	(30)	(33)
Fair value of plan assets at end of year	84	102	$ 122
Funded status at December 31	(994)	(1,144)
Other assets	0	0
Other accrued liabilities	(59)	(65)
Accrued pension costs	0	0
Accrued postretirement health care costs	(935)	(1,079)
Defined benefit plan, amounts for asset (liability) recognized in statement of financial position	$ (994)	$ (1,144)