Income Taxes - Summary of the activity related to the gross unrecognized tax benefits (excluding interest and penalties) (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits at beginning of year	$ 2,216	$ 2,110	$ 2,327
Increases in tax positions related to the current year	415	426	279
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	0	0	(193)
Decreases as a result of a lapse in applicable statute of limitations	(403)	(320)	(303)
Gross unrecognized tax benefits at end of year	$ 2,228	$ 2,216	$ 2,110

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

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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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- Definition

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

+ References

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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