Income taxes - Schedule of Domestic and Foreign Components of Loss before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure [Abstract]
Domestic	$ (340,542)	$ (191,479)	$ (372,466)
Foreign	12,660	4,248	4,873
Loss before provision for income taxes	$ (327,882)	$ (187,231)	$ (367,593)

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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- Definition

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

+ References

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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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