Revenue Recognition - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2020	Jul. 31, 2019
Revenues:
Revenues	$ 27,278	$ 27,383
Domestic
Revenues:
Revenues	23,140	21,411
International
Revenues:
Revenues	$ 4,138	$ 5,972

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