v3.23.1
Income taxes - Components of pre-tax loss (Details) - USD ($)
$ in Thousands
12 Months Ended
Sep. 30, 2022
Sep. 30, 2021
Sep. 30, 2020
Income Tax Disclosure [Abstract]      
US $ (231,659) $ (149,533) $ (138,016)
Foreign 3,385 (4,495) (1,533)
Loss before income taxes $ (228,274) $ (154,028) $ (139,549)