Inventories, net (Details) - USD ($)	Apr. 30, 2016	Apr. 30, 2015
Inventories, net
Raw materials	$ 11,609,000	$ 13,325,000
Work in process	4,259,000	5,140,000
Finished goods	26,073,000	25,537,000
Inventories, gross	41,941,000	44,002,000
Reserve for inventory excess and obsolescence	(4,455,000)	(4,588,000)
Inventories, net	37,486,000	39,414,000
Inventory consigned to others	$ 5,329,000	$ 6,840,000

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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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No definition available.

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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
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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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Gross amount of inventory owned by the entity but in the hands of a customer, typically a reseller.

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