Benefit Plans (Amounts Recorded in Accumulated Other Comprehensive Losses) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	$ (2,213)	$ (2,487)
Prior service (cost) credit	264	305
Deferred income taxes	513	570
Amounts recorded in accumulated other comprehensive losses	(1,436)	(1,612)
Pension [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	(2,180)	(2,093)
Prior service (cost) credit	(24)	(30)
Deferred income taxes	571	549
Amounts recorded in accumulated other comprehensive losses	(1,633)	(1,574)
Postretirement Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	1	(362)
Prior service (cost) credit	293	340
Deferred income taxes	(68)	12
Amounts recorded in accumulated other comprehensive losses	226	(10)
Postemployment Retirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	(34)	(32)
Prior service (cost) credit	(5)	(5)
Deferred income taxes	10	9
Amounts recorded in accumulated other comprehensive losses	$ (29)	$ (28)