Other Balance Sheet Information - Summary of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials and purchased parts	$ 67,428	$ 57,527
Work-in-process	13,799	19,547
Finished goods	28,843	19,912
Inventory, net	110,070	96,986
Reserves for excess and obsolete inventory	$ 14,900	$ 15,000

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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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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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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