Revenue - Disaggregated Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenue	$ 69,773	$ 49,109	$ 180,442	$ 130,933
North America
Disaggregation of Revenue [Line Items]
Total revenue	56,846	29,488	136,995	86,100
Europe, the Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenue	11,108	17,141	36,116	39,922
Asia Pacific
Disaggregation of Revenue [Line Items]
Total revenue	1,819	1,655	7,331	4,086
Rest of World
Disaggregation of Revenue [Line Items]
Total revenue	$ 0	$ 825	$ 0	$ 825
United States \| Revenue \| Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Geographic concentration risk, percentage	81.00%	60.00%	76.00%	65.00%
France \| Revenue \| Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Geographic concentration risk, percentage	8.00%	12.00%	11.00%	12.00%

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
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Balance Type:	credit
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