The Company - Additional Information (Detail) - USD ($) $ in Thousands	Jul. 31, 2022	Apr. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ 273,217	$ 250,175
Cash, cash equivalents and marketable securities	$ 142,100

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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant