Condensed Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (3,287)	$ 2,459	$ 4,526	$ 4,069
Other comprehensive income:
Net changes related to available-for-sale securities, net of tax	4	185	(3)	6
Foreign currency translation adjustments	524	794	588	1,067
Other comprehensive income	528	979	585	1,073
Comprehensive (loss) income	$ (2,759)	$ 3,438	$ 5,111	$ 5,142