Detail of Selected Balance Sheet Accounts - Components of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials, parts and subassemblies	$ 31,781	$ 24,563
Work-in-progress	1,100	1,080
Provision for excess and obsolete inventory	(3,679)	(4,291)
Total inventories	$ 29,202	$ 21,352

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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