Inventories, Net (Details) - Schedule of Inventory, Current - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Schedule of Inventory, Current [Abstract]
Raw Materials and Component Parts	$ 12,386	$ 15,470
Work in Progress	6,259	6,104
Finished Goods	1,016	1,384
	$ 19,661	$ 22,958

No definition available.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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