Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Current expense
Federal	$ 0	$ 0	$ 0
State	306	310	286
Foreign	369	479	418
Total	675	789	704
Deferred expense
Federal	0	0	0
State	0	0	0
Foreign	0	0	0
Total	0	0	0
Provision for income taxes	$ 675	$ 789	$ 704

Amount of current federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.

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