Inventories (Details) - Schedule of Inventory, Current - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Schedule of Inventory, Current [Abstract]
Raw Materials and Component Parts	$ 15,470	$ 11,600
Work in Progress	6,104	8,896
Finished Goods	1,384	2,860
	$ 22,958	$ 23,356

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(1))
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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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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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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