Inventories - Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Inventory Disclosure [Abstract]
Finished goods	$ 786us-gaap_InventoryFinishedGoods	$ 2,751us-gaap_InventoryFinishedGoods
Work in process	8,865us-gaap_InventoryWorkInProcess	5,932us-gaap_InventoryWorkInProcess
Purchased and manufactured parts	17,753	13,155
Inventories, gross	27,404us-gaap_InventoryGross	21,838us-gaap_InventoryGross
Reserve for slow moving and obsolescence	(2,953)us-gaap_InventoryValuationReserves	(2,929)us-gaap_InventoryValuationReserves
Total	$ 24,451us-gaap_InventoryNet	$ 18,909us-gaap_InventoryNet

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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.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.6(a)(1))

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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

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- Definition

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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-Section 02

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-Topic 210

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-Subparagraph (SX 210.5-02.6(a)(4),(5))

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Amount of valuation reserve for inventory.

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-Topic 210

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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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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