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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Goodwill And Other Intangibles (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Goodwill [Line Items]
Goodwill Impairment	$ 400	$ 400	$ 670
Infinite-lived intangible impairment		0
Impairment	$ 3,188	$ 3,188		$ 2,788
Customer Base [Member] \| Maximum [Member]
Goodwill [Line Items]
Estimated useful life		8 years
Customer Base [Member] \| Minimum [Member]
Goodwill [Line Items]
Estimated useful life		12 years