Income Taxes - Activity Related to Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 02, 2020	Jan. 31, 2019	Jan. 31, 2018
Reconciliation of Unrecognized Tax Benefits
Gross unrecognized tax benefits—beginning balance	$ 18,891	$ 12,401	$ 6,375
Decreases related to tax positions taken during prior years	(34)	(845)	(24)
Increases related to tax positions taken during prior years	408	0	619
Increases related to tax positions taken during current year	9,305	7,335	5,431
Gross unrecognized tax benefits—ending balance	$ 28,570	$ 18,891	$ 12,401

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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