- Goodwill and Other Intangible Assets Rollforward (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Changes in the net carrying amount of goodwill by operating segment
Beginning balance	$ 8,358
Goodwill related to current year acquisitions	31
Goodwill related to disposals	(1)
Goodwill related to prior year acquisitions	10
Foreign currency translation and other	(107)
Ending balance	$ 8,291

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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