Inventories, Net (Components Of Inventory) (Details) - USD ($)	Oct. 31, 2020	Apr. 30, 2020
Inventories, Net [Abstract]
Finished products	$ 22,153,570	$ 20,998,329
Work-in-process	4,483,188	5,215,280
Raw materials	58,544,737	62,316,122
Total inventory, gross	85,181,495	88,529,731
Less excess and obsolescence reserve	(1,241,315)	(1,350,362)
Total inventory, net	$ 83,940,180	$ 87,179,369

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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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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 of valuation reserve for inventory.

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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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