Restructuring and Other Costs, Net - Schedule of Restructuring and Other Costs, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Restructuring Cost And Reserve [Line Items]
Restructuring and other costs, net	$ 11,062	$ 705
Personnel
Restructuring Cost And Reserve [Line Items]
Restructuring and other costs, net	10,196	115
Facilities
Restructuring Cost And Reserve [Line Items]
Restructuring and other costs, net	0	145
Other
Restructuring Cost And Reserve [Line Items]
Restructuring and other costs, net	$ 866	$ 445