CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (2,285)	$ (3,672)	$ (15,378)	$ (8,818)
Other comprehensive income (loss):
Change in unrealized gains (losses) on available-for-sale securities, net of tax		(1)		82
Foreign currency translation adjustments	(235)	157	(686)	177
Total other comprehensive income (loss)	(235)	156	(686)	259
Total comprehensive loss	$ (2,520)	$ (3,516)	$ (16,064)	$ (8,559)