Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance, Amount at Sep. 30, 2020	$ 461,779	$ 195	$ 965,410	$ 18	$ (503,844)
Beginning Balance, Shares at Sep. 30, 2020		102,376,000
Stock-based compensation	8,144		8,144
Exercise of stock options, Amount	5,101		5,101
Exercise of stock options, Shares		538,000
Common stock - restricted stock units vesting, Shares		280,000
Foreign currency translation adjustments	180			180
Net income (loss)	(20,732)				(20,732)
Ending Balance, Amount at Dec. 31, 2020	454,472	$ 195	978,655	198	(524,576)
Ending Balance, Shares at Dec. 31, 2020		103,194,000
Beginning Balance, Amount at Sep. 30, 2021	408,822	$ 197	1,053,386	(69)	(644,692)
Beginning Balance, Shares at Sep. 30, 2021		104,327,000
Stock-based compensation	24,504		24,504
Exercise of stock options, Amount	$ 2,145		2,145
Exercise of stock options, Shares	207,814	208,000
Common stock - restricted stock units vesting, Shares		263,000
Foreign currency translation adjustments	$ (39)			(39)
Net income (loss)	(62,872)				(62,872)
Ending Balance, Amount at Dec. 31, 2021	$ 372,560	$ 197	$ 1,080,035	$ (108)	$ (707,564)
Ending Balance, Shares at Dec. 31, 2021		104,798,000