Supplementary Financial Information (Schedule Of Other Deductions And (Income)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Supplementary Financial Information [Abstract]
Professional fees	$ 2	$ 2
Recoverable pension and OPEB - non-service costs	13	13
AFUDC equity income	(6)	(6)
Interest and investment income	2	(3)
Other		1
Total other deductions and (income) - net	$ 11	$ 7