Property and equipment and right-of-use assets - Narrative (Details) - USD ($)	9 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Property, equipment, and right-of-use assets
Balance of equipment value paid in cash	$ 10,530,000	$ 6,852,000
Rental equipment
Property, equipment, and right-of-use assets
Rental equipment transferred from inventory	26,897,000	24,467,000
Accounts payable	1,756,000	0
Balance of equipment value paid in cash	8,949,000	5,056,000
Rental equipment \| Equipment loans
Property, equipment, and right-of-use assets
Principal amount of debt	$ 16,192,000	$ 19,411,000

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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Face (par) amount of debt instrument at time of issuance.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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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.

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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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