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Leases - Additional Information (Detail) - USD ($) |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2024 | Aug. 28, 2020 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2020
Lessee, Lease, Description [Line Items] |  |  |  |  |
Total rental expense |  |  | $ 47,000 | $ 47,000 |
Operating Lease, Expense |  |  | 432,000 | 429,000 |
Operating lease term |  | 3 years |  |  |
Operating leases paid in cash |  |  | 463,000 | 458,000 |
New Lease Agreement [Member] |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Assets |  | $ 352,000 | $ 330,000 | $ 328,000 | $ 970,000
Extended Lease Term 2024 [Member] |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Operating lease right of use asset | $ 361,000 |  |  |  |
Blaw Knox Product Line From Volvo CE [Member] | New Lease Agreement [Member] |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Operating lease liability date of expiry |  | Aug. 31, 2023 |  |  |
Blaw Knox Product Line From Volvo CE [Member] | Extended Lease Term 2024 [Member] |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Extended date of expiry of operating lease | Aug. 31, 2025 |  |  |  |

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- Definition Lessee operating lease lease right of use asset. + References No definition available. + Details
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- Definition Operating lease rental expenses one. + References No definition available. + Details
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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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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479041/842-20-45-4 + Details
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- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479041/842-20-45-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-4 + Details
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