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Goodwill And Other Intangibles (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Goodwill [Line Items]
Impairment		$ 9,154		$ 9,154
Goodwill				$ 658
Goodwill impairment	$ 276		$ 5,725
Customer Base [Member] \| Maximum [Member]
Goodwill [Line Items]
Useful life		12 years
Customer Base [Member] \| Minimum [Member]
Goodwill [Line Items]
Useful life		8 years