Goodwill And Other Intangibles (Schedule Of Goodwill Activity) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill And Other Intangibles [Abstract]
Goodwill, Beginning Balance	$ 6,383	$ 7,024
Reclassified as held for sale	(658)
Goodwill impairment	$ (5,725)	(641)	$ (2,748)
Goodwill, Ending Balance		$ 6,383	$ 7,024

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Period Type:	duration