Summary of Accounting Policies (Details) - Revenue from External Customers by Products and Services - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021
Revenue from External Customer [Line Items]
Revenue	$ 48,296	$ 54,254
Satellite Revenue [Member]
Revenue from External Customer [Line Items]
Revenue	26,092	26,980
Government Non-Space Revenue [Member]
Revenue from External Customer [Line Items]
Revenue	19,593	24,775
Other Commercial & Industrial Revenue [Member]
Revenue from External Customer [Line Items]
Revenue	$ 2,611	$ 2,499

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details