Goodwill and Other Intangible Assets and Liablities Goodwill Impairment and Carrying Value (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2018
Goodwill [Line Items]
Incurred impairment losses related to Goodwill	$ 0	$ 0	$ 0
Accumulated impairment losses related to Goodwill	0	0
Carrying value of goodwill	14,851	$ 14,845		$ 6
Additional Goodwill recognized	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

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