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

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.

+ Details

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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
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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)
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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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- Details

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- Details

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ACQUISITIONS/DIVESTITURES - Businesses Acquired, 2017 (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) entity	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
ACQUISITIONS
Goodwill	$ 36,788	$ 36,199	$ 32,021
Technology Services & Cloud Platforms
ACQUISITIONS
Goodwill	10,447	10,258	10,156
Cognitive Solutions
ACQUISITIONS
Goodwill	19,665	19,484	15,621
Global Business Services
ACQUISITIONS
Goodwill	$ 4,813	$ 4,607	$ 4,396
2017 Acquisitions
ACQUISITIONS
Businesses acquired, number (in entities) \| entity	5
Businesses acquired, aggregate cost	$ 134
Percentage of business acquired (as a percent)	100.00%
Goodwill	$ 16
Expected percent of goodwill deductible for tax purposes	50.00%
2017 Acquisitions \| Technology Services & Cloud Platforms
ACQUISITIONS
Businesses acquired, number (in entities) \| entity	3
Goodwill	$ 13
2017 Acquisitions \| Cognitive Solutions
ACQUISITIONS
Businesses acquired, number (in entities) \| entity	1
Goodwill	$ 3
2017 Acquisitions \| Global Business Services
ACQUISITIONS
Businesses acquired, number (in entities) \| entity	1