The Company - Additional Information (Detail) - USD ($) $ in Thousands	Jul. 31, 2020	Apr. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit	$ 132,406	$ 121,592
Cash, cash equivalents and marketable securities	$ 64,300

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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