Detail of Selected Balance Sheet Accounts - Components of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials, parts and subassemblies	$ 24,563	$ 22,100
Work-in-progress	1,080	600
Provision for excess and obsolete inventory	(4,291)	(4,252)
Total inventories	$ 21,352	$ 18,448

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

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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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