Geographical Information (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 305,420	$ 276,057	$ 234,989
United States
Disaggregation of Revenue [Line Items]
Total revenue	200,273	190,208	168,221
Others
Disaggregation of Revenue [Line Items]
Total revenue	$ 105,147	$ 85,849	$ 66,768
Revenue \| Geographic Concentration \| United States
Disaggregation of Revenue [Line Items]
Concentration risk (percent)	66.00%	69.00%	72.00%
Revenue \| Geographic Concentration \| Others
Disaggregation of Revenue [Line Items]
Concentration risk (percent)	34.00%	31.00%	28.00%

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details