Income taxes (Details) - USD ($)	3 Months Ended	9 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income taxes
Provision for income taxes	$ 35,000	$ 0	$ 99,000	$ 483,000

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details