Components of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Inventory [Line Items]
Raw materials and supplies	$ 6,707	$ 6,267
Work-in-progress	6,672	5,296
Finished goods	2,257	3,367
Inventories	$ 15,636	$ 14,930

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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-Subparagraph (SX 210.5-02.6(a))

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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