Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (27,274)	$ 4,237	$ 1,123
Other comprehensive (loss) income:
Net changes related to available-for-sale securities, net of tax	(1)	1	(10)
Foreign currency translation adjustments	(11,600)	(1,448)	2,788
Other comprehensive (loss) income	(11,601)	(1,447)	2,778
Comprehensive (loss) income	$ (38,875)	$ 2,790	$ 3,901