Acquisitions (Schedule Of Acquired Finite-Lived Intangible Assets By Major Class) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Goodwill [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Beginning Balance	$ 309
Measurement period adjustments	4
Ending Balance	314
Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Beginning Balance	31	[1]
Ending Balance	31	[1]
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Beginning Balance	197	[2]
Measurement period adjustments	(4)	[2]
Ending Balance	$ 192	[2]

[1] Subject to amortization.

[2] Primarily customer lists.