Pension And Postretirement Benefits (Change In The Projected Benefit Obligation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Actuarial (gain) loss	$ (1,999)	$ (4,143)	$ 4,169
Pension Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	57,212	62,158
Service cost - benefits earned during the period	617	957	1,029
Interest cost on projected benefit obligation	1,747	1,276	1,687
Amendments	0	0
Actuarial (gain) loss	(10,894)	(1,237)
Benefits paid, including settlements	(5,854)	(5,942)
Benefit obligation at end of year	42,828	57,212	62,158
Postretirement Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	12,552	13,928
Service cost - benefits earned during the period	32	45	53
Interest cost on projected benefit obligation	277	210	416
Amendments	(2,370)	0
Actuarial (gain) loss	(1,919)	(275)
Benefits paid, including settlements	(1,292)	(1,356)
Benefit obligation at end of year	$ 7,280	$ 12,552	$ 13,928