v3.20.1

Income taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits at beginning of year	$ 1,693	$ 889
Increases as a result of tax positions taken during a prior period	6,888	0
Decreases as a result of tax positions taken during a prior period	(1)	(1)
Increases as a result of tax positions taken during the current period	790	805
Decreases as a result of tax positions taken during the current period	0	0
Decreases resulting from the lapse of the applicable statute of limitations	0	0
Gross unrecognized tax benefits at end of year	9,370	1,693
Total gross unrecognized tax benefits	$ 9,370	$ 889	$ 9,370	$ 1,693
Amounts netted against related deferred tax assets			(8,914)	(1,693)
Unrecognized tax benefits recorded on the consolidated balance sheet			$ 456	$ 0

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- Definition

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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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- Definition

Amount of unrecognized tax benefits.

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

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