Other Balance Sheet Information Summary of Inventories (Detail) (USD $)	Dec. 31, 2014	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials and purchased parts	$ 58,034,000us-gaap_InventoryRawMaterials	$ 57,250,000us-gaap_InventoryRawMaterials
Work-in-process	20,538,000us-gaap_InventoryWorkInProcess	20,068,000us-gaap_InventoryWorkInProcess
Finished goods	16,364,000us-gaap_InventoryFinishedGoods	16,249,000us-gaap_InventoryFinishedGoods
Inventory, net	94,936,000us-gaap_InventoryNet	93,567,000us-gaap_InventoryNet
Reserves for excess and obsolete inventory	$ 25,900,000us-gaap_InventoryValuationReserves	$ 26,000,000us-gaap_InventoryValuationReserves

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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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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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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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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