Note 8 - Leases - Rental Equipment (Details) - Equipment [Member] - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Rental equipment, primarily wireless recording equipment	$ 79,479	$ 83,887
Accumulated depreciation and impairment	(58,900)	(55,688)
Property, Plant, and Equipment, Lessor Asset under Operating Lease, after Accumulated Depreciation	$ 20,579	$ 28,199

Amount of accumulated depreciation of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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