The aggregate of property, plant and equipment and other noncurrent assets recognized as of the acquisition date.

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Amount of assets acquired at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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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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Acquisitions/Divestitures - 2017 Purchase Price Allocation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2016
Acquisitions
Goodwill	$ 36,788	$ 36,265	$ 36,199
2017 Acquisitions
Acquisitions
Current assets	18
Fixed assets/noncurrent assets	69
Goodwill	16
Total assets acquired	177
Current liabilities	(9)
Noncurrent liabilities	(34)
Total liabilities assumed	(43)
Total purchase price	$ 134
Acquired intangible asset, weighted average useful life	6 years 7 months 6 days
2017 Acquisitions \| Completed technology
Acquisitions
Intangible assets	$ 9
Acquired intangible asset, weighted average useful life	5 years
2017 Acquisitions \| Client relationships
Acquisitions
Intangible assets	$ 64
2017 Acquisitions \| Client relationships \| Minimum
Acquisitions
Acquired intangible asset, weighted average useful life	5 years
2017 Acquisitions \| Client relationships \| Maximum
Acquisitions
Acquired intangible asset, weighted average useful life	7 years
2017 Acquisitions \| Patents/trademarks
Acquisitions
Intangible assets	$ 1
2017 Acquisitions \| Patents/trademarks \| Minimum
Acquisitions
Acquired intangible asset, weighted average useful life	1 year
2017 Acquisitions \| Patents/trademarks \| Maximum
Acquisitions
Acquired intangible asset, weighted average useful life	5 years