Acquisitions (Schedule Of Acquired Finite-Lived Intangible Assets By Major Class) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Goodwill [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Beginning Balance	$ 179
Measurement period adjustments	(2)
Ending Balance	177
Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Measurement period adjustments	13	[1]
Ending Balance	13	[1]
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Beginning Balance	80
Measurement period adjustments	(13)
Ending Balance	$ 67

[1] Not subject to amortization