Leases - Summary of Other Information Concerning the Company's Operating Lease (Detail) - USD ($)	Dec. 31, 2025	Sep. 30, 2025	Sep. 30, 2020	Aug. 28, 2020
Lessee, Lease, Description [Line Items]
Current operating lease liability	$ 248,000	$ 339,000
New Lease Agreement [Member]
Lessee, Lease, Description [Line Items]
Operating lease ROU asset included in other long-term assets	248,000	339,000	$ 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	$ 248,000	$ 339,000
Weighted average remaining lease term (in years)	8 months 1 day	11 months 1 day
Weighted average discount rate used in calculating ROU asset	4.50%	4.50%