Components of Other Selected Captions in Consolidated Balance Sheets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011
Other Assets and Other Liabilities [Line Items]
Accounts receivable	$ 81,175	$ 77,318
Less allowances	683	617
Accounts receivable, net	80,492	76,701
Inventories, net
Raw materials and purchased parts	68,865	65,770
Work-in-process	23,539	29,460
Finished goods	12,661	12,424
Inventories, net	$ 105,065	$ 107,654

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Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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Carrying amount 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 (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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Carrying amount as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

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Carrying amount as of the balance sheet date of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and 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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