Acquisitions (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($) entity
Acquisitions
Number of acquisitions	2
Aggregate acquisitions cost \| $	$ 49
Percentage of business acquired (as a percent)	100.00%
Cognitive Solutions
Acquisitions
Number of acquisitions	1
Global Business Services
Acquisitions
Number of acquisitions	1

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No definition available.

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

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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.

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- Definition

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

+ References

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