The percent of goodwill arising from a business combination that is expected to be deductible for tax purposes.

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB
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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Details

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ACQUISITIONS/DIVESTITURES - Businesses Acquired, 2016 (Details) $ in Millions			1 Months Ended		12 Months Ended
	Apr. 08, 2016 USD ($)	Jan. 29, 2016 USD ($)	Jul. 31, 2017 USD ($)	Apr. 30, 2016 USD ($)	Dec. 31, 2016 USD ($) entity	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)
ACQUISITIONS
Goodwill					$ 36,199	$ 36,788	$ 32,021
Technology Services & Cloud Platforms
ACQUISITIONS
Goodwill					10,258	10,447	10,156
Global Business Services
ACQUISITIONS
Goodwill					4,607	4,813	4,396
Cognitive Solutions
ACQUISITIONS
Goodwill					$ 19,484	$ 19,665	$ 15,621
2016 Acquisitions
ACQUISITIONS
Businesses acquired, number (in entities) \| entity					15
Businesses acquired, aggregate cost					$ 5,899
The Weather Company
ACQUISITIONS
Businesses acquired, cash consideration		$ 2,278
Goodwill		$ 1,717
Expected percent of goodwill deductible for tax purposes		0.00%
Acquired intangible asset, weighted average useful life		6 years 10 months 24 days
The Weather Company \| Cognitive Solutions
ACQUISITIONS
Goodwill		$ 1,717
Truven Health Analytics
ACQUISITIONS
Businesses acquired, aggregate cost	$ 2,612
Percentage of business acquired (as a percent)	100.00%
Businesses acquired, cash consideration			$ 148	$ 2,412
Goodwill	$ 1,933
Expected percent of goodwill deductible for tax purposes	15.00%
Acquired intangible asset, weighted average useful life	6 years 10 months 24 days
Truven Health Analytics \| Cognitive Solutions
ACQUISITIONS
Goodwill	$ 1,933
Other 2016 Acquisitions
ACQUISITIONS
Percentage of business acquired (as a percent)					100.00%
Goodwill					$ 593
Expected percent of goodwill deductible for tax purposes					55.00%
Acquired intangible asset, weighted average useful life					6 years 3 months 18 days
Other 2016 Acquisitions \| Technology Services & Cloud Platforms
ACQUISITIONS
Businesses acquired, number (in entities) \| entity					4
Goodwill					$ 119
Other 2016 Acquisitions \| Global Business Services
ACQUISITIONS
Businesses acquired, number (in entities) \| entity					6
Goodwill					$ 303
Other 2016 Acquisitions \| Cognitive Solutions
ACQUISITIONS
Businesses acquired, number (in entities) \| entity					3
Goodwill					$ 171