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Leases - Summary of Other Information Concerning the Company's Operating Lease (Detail) - USD ($) | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2020 | Aug. 28, 2020
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Lessee, Lease, Description [Line Items] |  |  |  |
Current operating lease liability | $ 330,000 | $ 328,000 |  |
New Lease Agreement [Member] |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |
Operating lease ROU asset included in other long-term assets | 330,000 | 328,000 | $ 970,000 | $ 352,000
Blaw Knox Product Line From Volvo CE [Member] | New Lease Agreement [Member] |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |
Current operating lease liability | $ 330,000 | $ 328,000 |  |
Weighted average remaining lease term (in years) | 11 months 1 day | 6 months 3 days |  |
Weighted average discount rate used in calculating ROU asset | 5.00% | 4.50% |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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