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

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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 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 - Purchase Price Allocation (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
ACQUISITIONS
Goodwill	$ 36,782	$ 36,199	$ 32,021
2017 Acquisitions
ACQUISITIONS
Current assets	18
Fixed assets/noncurrent assets	69
Goodwill	16
Total assets acquired	175
Current liabilities	(47)
Total liabilities assumed	(47)
Total purchase price	$ 128
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	$ 62
Acquired intangible asset, weighted average useful life	7 years
2017 Acquisitions \| Patents/trademarks
ACQUISITIONS
Intangible assets	$ 1
Minimum \| 2017 Acquisitions \| Patents/trademarks
ACQUISITIONS
Acquired intangible asset, weighted average useful life	1 year
Maximum \| 2017 Acquisitions \| Patents/trademarks
ACQUISITIONS
Acquired intangible asset, weighted average useful life	5 years