Summary of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2014	Apr. 30, 2014
Inventory [Line Items]
Finished goods	$ 36,522	$ 26,523
Finished parts	51,837	47,109
Work in process	6,251	7,643
Raw material	6,707	5,467
Total inventories	$ 101,317	$ 86,742

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of items purchased for use as components of a finished product or pieces of machinery and equipment plus any items in their natural and unrefined state. This element may be used when the reporting entity combines raw materials and purchased parts into an aggregate amount.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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