Summary of Significant Accounting Policies and Select Balance Sheet Information - Components of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 3,758	$ 2,034
Work-in process	817	892
Finished products	1,391	1,575
Total	$ 5,966	$ 4,501

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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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-Topic 210
-SubTopic 10
-Section S99
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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 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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-Publisher FASB
-Name Accounting Standards Codification
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