Income Taxes - Components of Income (Loss) Before Provisions (Benefit) For Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure [Abstract]
Domestic	$ 686	$ 839	$ 160
Foreign	20	144	260
Income before benefit from (provision for) income taxes	$ 706	$ 983	$ 420

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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- References

No definition available.

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