Provision for Income Taxes - Components of Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021
Federal
Current	$ 0	$ 0
Total	0	0
State
Current	10	13
Total	10	13
Foreign
Current	25	62
Total	25	62
Current, total	35	75
Provision for income tax	$ 35	$ 75

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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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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