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Leases - Summary of Other Information Concerning the Company's Operating Lease (Detail) - USD ($)	Sep. 30, 2021	Oct. 09, 2020	Sep. 30, 2020	Aug. 28, 2020
Lessee, Lease, Description [Line Items]
Operating lease ROU asset included in other long-term assets				$ 970,000
Current operating lease liability	$ 393,000		$ 328,000
Non-current operating lease liability	392,000		614,000
New Lease Agreement [Member]
Lessee, Lease, Description [Line Items]
Operating lease ROU asset included in other long-term assets		$ 254,000
Blaw Knox Product Line From Volvo CE [Member] | New Lease Agreement [Member]
Lessee, Lease, Description [Line Items]
Operating lease ROU asset included in other long-term assets	785,000		942,000
Current operating lease liability	393,000		328,000
Non-current operating lease liability	$ 392,000		$ 614,000
Weighted average remaining lease term (in years)	2 years		2 years 11 months 1 day
Weighted average discount rate used in calculating ROU asset	4.00%		4.00%

X

- 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

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-SubTopic 20
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