Revenue - Disaggregated Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2021	Jul. 31, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 52,406	$ 40,483
North America
Disaggregation of Revenue [Line Items]
Total revenue	36,452	28,805
Europe, the Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenue	12,219	10,253
Asia Pacific
Disaggregation of Revenue [Line Items]
Total revenue	$ 3,735	$ 1,425
United States \| Revenue \| Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Geographic concentration risk, percentage	69.00%	71.00%
France \| Revenue \| Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Geographic concentration risk, percentage	13.00%	11.00%

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration