Debt - Schedule of Debt Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Gross Amount	$ 530,000	$ 333,373
Gross Amount, current portion	0	103,373
Gross Amount, excluding current maturities	530,000	230,000
Debt Issuance Costs	(11,924)	(6,045)
Debt Issuance Costs, current portion	0	(301)
Debt Issuance Costs, excluding current portion	(11,924)	(5,744)
Carrying Amount	518,076	327,328
Carrying Amount, excluding current portion	0	103,072
Carrying Amount	518,076	224,256
Senior Notes
Debt Instrument [Line Items]
Gross Amount	530,000
Senior Notes | 2032 Senior Notes
Debt Instrument [Line Items]
Gross Amount	300,000	0
Debt Issuance Costs	(7,182)	0
Carrying Amount	292,818	0
Senior Notes | 2029 Convertible Notes
Debt Instrument [Line Items]
Gross Amount	230,000	230,000
Debt Issuance Costs	(4,742)	(5,744)
Carrying Amount	225,258	224,256
Senior Notes | 2025 Convertible Notes
Debt Instrument [Line Items]
Gross Amount	0	103,373
Debt Issuance Costs	0	(301)
Carrying Amount	$ 0	$ 103,072