Summary of Significant Accounting Policies and Select Balance Sheet Information - Components of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 4,165	$ 3,758
Work-in process	1,295	817
Finished products	1,300	1,391
Total	$ 6,760	$ 5,966

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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 merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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