Intangible Assets Acquired Through Business Combinations and Goodwill (Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 12,851	$ 7,314
Goodwill acquired		5,536
Other acquisitions and adjustments	29	1
Goodwill, ending balance	25,134	$ 12,851
Tableau Software, Inc.
Goodwill [Roll Forward]
Goodwill acquired	10,806
ClickSoftware Technologies Ltd.
Goodwill [Roll Forward]
Goodwill acquired	1,132
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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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