Inventories, Net (Components Of Inventory) (Details) (USD $)	Jul. 31, 2014	Apr. 30, 2014
Inventories, Net [Abstract]
Finished products	$ 22,577,250	$ 18,553,112
Work-in-process	3,135,634	3,126,596
Raw materials	33,588,822	33,853,653
Total inventory, gross	59,301,706	55,533,361
Less obsolescence reserve	1,756,369	1,804,984
Total inventory, net	$ 57,545,337	$ 53,728,377

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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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