Retirement Benefits (Reconciliation Of The Benefit Obligation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits [Member]
Reconciliation of benefit obligation
Benefit obligation at beginning of year	$ 2,009	$ 1,880
Service cost	0	0
Interest cost	34	47	$ 62
Plan participant contributions	0	0
Actuarial loss (gain)	(33)	219
Settlements	(90)	(80)
Benefits paid	(61)	(57)
Benefit obligation at end of year	1,859	2,009	1,880
Other Benefits [Member]
Reconciliation of benefit obligation
Benefit obligation at beginning of year	399	423
Service cost	1	1	1
Interest cost	5	10	15
Plan participant contributions	17	18
Actuarial loss (gain)	(31)	(15)
Settlements	0	0
Benefits paid	(48)	(38)
Benefit obligation at end of year	$ 343	$ 399	$ 423