Represents the number of divestitures completed during the period.

No definition available.

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- Definition

Percentage received at closing of the total cash consideration from the sale of a portion of the company's business.

+ References

No definition available.

+ Details

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- Definition

Period after closing for receipt of the remaining cash consideration from the sale of a portion of the company's business.

+ References

No definition available.

+ Details

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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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

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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Acquisitions/Divestitures - Divestitures (Details) $ in Millions	3 Months Ended						6 Months Ended	12 Months Ended
	Dec. 31, 2017 item	Sep. 30, 2017 item	Jun. 30, 2017 item	Mar. 31, 2017 item	Dec. 31, 2016 item	Mar. 31, 2016 item	Jun. 30, 2019 USD ($)	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)
Select Standalone Cognitive Solutions Software Products \| Expected
Divestitures
Cash consideration \| $							$ 1,775
Consideration receivable at closing (as a percent)							50.00%
Select Standalone Cognitive Solutions Software Products \| Expected \| Minimum
Divestitures
Period after closing for receipt of remaining consideration							12 months
Select Standalone Cognitive Solutions Software Products \| Expected \| Maximum
Divestitures
Period after closing for receipt of remaining consideration							15 months
Others
Divestitures
Pre-tax gain on sale of business \| $								$ 31	$ 42
Research-Related Divestitures
Divestitures
Number of divestitures				1
Cognitive Solutions Divestitures
Divestitures
Number of divestitures	1	1	2					4
Software Product-Related Divestitures
Divestitures
Number of divestitures						4
Service-Related Offerings
Divestitures
Number of divestitures					1