Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Revenues	[1]	$ 312,974	$ 245,109	$ 203,565
Operating expenses:
Cost of revenues		179,625	155,380	119,330
Research and development		90,852	106,894	120,307
Selling, general and administrative		218,398	189,738	212,949
Restructuring and other costs		0	9,384	0
Change in fair value of contingent considerations and holdbacks		0	(5,913)	(14,245)
Impairment of long-lived assets		44,930	6,785	0
Total operating expenses		533,805	462,268	438,341
Loss from operations		(220,831)	(217,159)	(234,776)
Interest income		15,344	14,365	3,062
Interest expense		(29)	(5)	(80)
Gain on deconsolidation of subsidiary		0	0	4,607
Other income (expense), net		(2,650)	(667)	(1,087)
Loss before income taxes		(208,166)	(203,466)	(228,274)
Income tax (expense) benefit		(560)	(1,152)	10,411
Net loss attributable to common stockholders		(208,726)	(204,618)	(217,863)
Other comprehensive income (loss):
Change in unrealized gain (loss) on investments		203	1,510	(1,594)
Foreign currency translation adjustment		31	(423)	(795)
Comprehensive loss		$ (208,492)	$ (203,531)	$ (220,252)
Net loss per share attributable to common stockholders—basic (in dollars per share)		$ (3.60)	$ (3.60)	$ (4.04)
Net loss per share attributable to common stockholders—diluted (in dollars per share)		$ (3.60)	$ (3.60)	$ (4.04)
Weighted average shares used in computing net loss per share attributable to common stockholders—basic (in shares)		58,016	56,885	53,885
Weighted average shares used in computing net loss per share attributable to common stockholders—diluted (in shares)		58,016	56,885	53,885

[1] During the years ended September 30, 2024, 2023 and 2022, the Company had revenues from related parties in the amount of $12.1 million, $5.9 million and $3.5 million, respectively.