Inventories, Net (Components Of Inventory) (Details) - USD ($)	Oct. 31, 2015	Apr. 30, 2015
Inventories, Net [Abstract]
Finished products	$ 24,631,107	$ 24,316,404
Work-in-process	3,269,704	2,966,846
Raw materials	40,672,952	42,662,845
Total inventory, gross	68,573,763	69,946,095
Less obsolescence reserve	1,216,990	1,276,386
Total inventory, net	$ 67,356,773	$ 68,669,709

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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.6(a))
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-Topic 330
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-Section 35
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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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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