Postretirement Plans (Schedule Of Estimated Future Benefit Payments) (Details) $ in Millions	Dec. 31, 2021 USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Year One	$ 4,839
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	4,723
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	4,657
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	4,578
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	4,481
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years	20,713
Other Postretirement Benefits Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Year One	421
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	396
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	375
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	353
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	329
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years	1,261
Defined Benefit Plan Expected Future Gross Benefit Payments In Year One	450
Defined Benefit Plan Expected Future Gross Benefit Payments In Year Two1	425
Defined Benefit Plan Expected Future Gross Benefit Payments In Year Three1	404
Defined Benefit Plan Expected Future Gross Benefit Payments In Year Four1	380
Defined Benefit Plan Expected Future Gross Benefit Payments In Year Five1	356
Defined Benefit Plan Expected Future Gross Benefit Payments In Year Thereafter1	1,385
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, Year One	(29)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, Year Two	(29)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, Year Three	(29)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, Year Four	(27)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, Year Five	(27)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt, after Year Five	$ (124)