CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - 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	$ (787)	$ (2,285)	$ (9,021)	$ (15,378)
Other comprehensive income (loss):
Change in unrealized losses on available-for-sale securities, net of tax	(6)		(9)
Foreign currency translation adjustments	278	(235)	541	(686)
Total other comprehensive income (loss)	272	(235)	532	(686)
Total comprehensive loss	$ (515)	$ (2,520)	$ (8,489)	$ (16,064)