Revenue Recognition - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2021	Jul. 31, 2020
Revenues:
Revenues	$ 29,271	$ 27,278
Domestic
Revenues:
Revenues	24,427	23,140
International
Revenues:
Revenues	$ 4,844	$ 4,138

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