Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net loss	$ (39,065)	$ (31,700)	$ (105,709)	$ (95,407)
Other comprehensive income (loss):
Net unrealized gains (losses) on marketable securities	311	(583)	2,220	(3,238)
Total other comprehensive income (loss)	311	(583)	2,220	(3,238)
Comprehensive loss	$ (38,754)	$ (32,283)	$ (103,489)	$ (98,645)