Goodwill And Other Intangibles (Goodwill Rollforward) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Goodwill And Other Intangibles [Abstract]
Goodwill, Beginning Balance				$ 6,383
Reclassification as held for sale				(658)
Goodwill impairment	$ (276)	$ (5,449)	$ (400)	$ (5,725)	$ (400)

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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