Goodwill and Other Intangible Assets - Schedule of changes in the net carrying amount of goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Changes in the net carrying amount of goodwill (in millions)
Balance at the beginning of the period	$ 8,171	$ 8,358
Goodwill related to current year acquisitions	34	38
Goodwill related to disposals	(11)	(2)
Goodwill related to prior year acquisitions	2	4
Foreign currency translation	(31)	(227)
Balance at the end of the period	$ 8,165	$ 8,171

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 foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of divestiture 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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