Acquisitions & Divestitures - 2019 Acquisitions (Details) $ / shares in Units, $ in Billions		12 Months Ended
Jul. 09, 2019 USD ($) $ / shares	Dec. 31, 2019 USD ($) item
2019 Acquisitions
Acquisitions
Aggregate acquisitions cost		$ 35
Red Hat, Inc.
Acquisitions
Aggregate acquisitions cost	$ 35
Percentage of business acquired (as a percent)	100.00%
Cash paid to acquiree shareholders (in dollars per share) \| $ / shares	$ 190
Equity value	$ 34
Software \| Red Hat, Inc.
Acquisitions
Number of acquisitions \| item		1

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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

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