Intangible Assets Acquired Through Business Combinations and Goodwill (Goodwill) (Details) $ in Millions	9 Months Ended
Oct. 31, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of January 31, 2019	$ 12,851
Other acquisitions and adjustments	6
Balance as of October 31, 2019	25,022
Tableau Software, Inc.
Goodwill [Roll Forward]
Goodwill acquired	10,723
ClickSoftware Technologies Ltd.
Goodwill [Roll Forward]
Goodwill acquired	1,126
Balance as of October 31, 2019	1,126
Salesforce.org
Goodwill [Roll Forward]
Goodwill acquired	164
MapAnything, Inc.
Goodwill [Roll Forward]
Goodwill acquired	$ 152

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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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