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Leases - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Oct. 31, 2021	Sep. 30, 2021	Oct. 09, 2020	Aug. 28, 2020
Lessee, Lease, Description [Line Items]
Operating Lease, Expense	$ 101,000		$ 105,000	$ 202,000	$ 194,000
Operating lease term									3 years
Operating leases paid in cash		$ 107,000	$ 116,000	216,000	$ 232,000
New Lease Agreement [Member]
Lessee, Lease, Description [Line Items]
Assets								$ 254,000	$ 970,000
New Lease Agreement [Member] | Renewal Event
Lessee, Lease, Description [Line Items]
Assets						$ 39,000
New Lease Agreement [Member] | Square Footage Leased Event [Member]
Lessee, Lease, Description [Line Items]
Decrease In Leasing Arrangements Right Of Use Asset And Lease Liability				39,000
Blaw Knox Product Line From Volvo CE [Member] | New Lease Agreement [Member]
Lessee, Lease, Description [Line Items]
Assets	$ 596,000			$ 596,000			$ 785,000
Operating lease term								1 year

X

- Definition

Decrease in leasing arrangements right of use asset and lease liability .

+ 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

No definition available.

+ Details

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X

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980

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X

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

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- Definition

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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