Provision for Income Taxes - Components of Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2021	Apr. 30, 2020
Federal
Current		$ 0
Total		0
State
Current	$ 13	3
Total	13	3
Foreign
Current	62	127
Total	62	127
Current, total	75	130
Provision for income tax	$ 75	$ 130

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

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