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Nature of Operations and Summary of Significant Accounting Policies - Schedule of Changes in Allowance for Slow Moving and Obsolete Inventories (Detail) - USD ($) | 12 Months Ended
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Sep. 30, 2024 | Sep. 30, 2023
Inventory Disclosure [Abstract] |  |
Balance, beginning of year | $ 9,813,000 | $ 8,192,000
Charged to cost of sales | 3,834,000 | 2,147,000
Disposal of inventory, net of recoveries | (316,000) | (526,000)
Balance, end of year | $ 13,331,000 | $ 9,813,000

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- Definition Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 330 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483080/330-10-50-2 + Details
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