Condensed Consolidated Statements of Stockholders’ Equity (unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional paid-in capital	Accumulated Other comprehensive income	Accumulated deficit
Beginning balance (in shares) at Sep. 30, 2020		45,083
Beginning balance at Sep. 30, 2020	$ 336,262	$ 0	$ 794,630	$ 87	$ (458,455)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses (in shares)		3,136
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses	323,887		323,887
Net exercise of stock warrants (in shares)		22
Vesting of restricted stock units (in shares)		121
Exercise of stock options (in shares)		497
Exercise of stock options	9,137		9,137
Issuance of shares under the employee stock purchase plan (in shares)		49
Issuance of shares under the employee stock purchase plan	2,787		2,787
Repurchases of early exercised stock options (in shares)		(2)
Repurchases of common stock for income tax withholding (in shares)		(46)
Repurchases of common stock for income tax withholding	(5,751)		(5,751)
Stock-based compensation	18,575		18,575
Other comprehensive income	103			103
Net loss	(70,819)				(70,819)
Ending balance (in shares) at Mar. 31, 2021		48,860
Ending balance at Mar. 31, 2021	614,181	$ 0	1,143,265	190	(529,274)
Beginning balance (in shares) at Dec. 31, 2020		48,616
Beginning balance at Dec. 31, 2020	637,952	$ 0	1,129,165	142	(491,355)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Public offering expense adjustment	36		36
Vesting of restricted stock units (in shares)		67
Exercise of stock options (in shares)		152
Exercise of stock options	3,066		3,066
Issuance of shares under the employee stock purchase plan (in shares)		49
Issuance of shares under the employee stock purchase plan	2,787		2,787
Repurchases of early exercised stock options (in shares)		(2)
Repurchases of common stock for income tax withholding (in shares)		(22)
Repurchases of common stock for income tax withholding	(3,341)		(3,341)
Stock-based compensation	11,552		11,552
Other comprehensive income	48			48
Net loss	(37,919)				(37,919)
Ending balance (in shares) at Mar. 31, 2021		48,860
Ending balance at Mar. 31, 2021	614,181	$ 0	1,143,265	190	(529,274)
Beginning balance (in shares) at Sep. 30, 2021		49,499
Beginning balance at Sep. 30, 2021	580,821	$ 0	1,190,828	546	(610,553)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses (in shares)		5,227
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses	269,818		269,818
Vesting of restricted stock units (in shares)		163
Exercise of stock options (in shares)		368
Exercise of stock options	3,934		3,934
Issuance of shares under the employee stock purchase plan (in shares)		50
Issuance of shares under the employee stock purchase plan	2,395		2,395
Repurchases of common stock for income tax withholding (in shares)		(62)
Repurchases of common stock for income tax withholding	(4,050)		(4,050)
Issuance of shares from business acquisition (in shares)		989
Issuance of shares from business acquisition	77,122		77,122
Stock-based compensation	40,573		40,573
Other comprehensive income	(1,021)			(1,021)
Net loss	(106,231)				(106,231)
Ending balance (in shares) at Mar. 31, 2022		56,234
Ending balance at Mar. 31, 2022	863,361	$ 0	1,580,620	(475)	(716,784)
Beginning balance (in shares) at Dec. 31, 2021		50,735
Beginning balance at Dec. 31, 2021	626,178	$ 0	1,281,931	363	(656,116)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses (in shares)		5,227
Issuance of common stock in public offering, net of underwriting discounts and commissions and offering expenses	269,818		269,818
Vesting of restricted stock units (in shares)		100
Exercise of stock options (in shares)		100
Exercise of stock options	896		896
Issuance of shares under the employee stock purchase plan (in shares)		50
Issuance of shares under the employee stock purchase plan	2,395		2,395
Repurchases of common stock for income tax withholding (in shares)		(38)
Repurchases of common stock for income tax withholding	(1,493)		(1,493)
Issuance of shares from business acquisition (in shares)		60
Issuance of shares from business acquisition	4,608		4,608
Stock-based compensation	22,465		22,465
Other comprehensive income	(838)			(838)
Net loss	(60,668)				(60,668)
Ending balance (in shares) at Mar. 31, 2022		56,234
Ending balance at Mar. 31, 2022	$ 863,361	$ 0	$ 1,580,620	$ (475)	$ (716,784)