Leases - Schedule of Lease Assets and Liabilities and Lease Cost (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Sep. 30, 2025 |
|
| Lease Assets and Liabilities | |||||
| Operating lease assets | $ 55,667 | $ 55,667 | $ 43,891 | ||
| Current operating lease liabilities | 5,322 | 5,322 | 7,289 | ||
| Non-current operating lease liabilities | 114,298 | 114,298 | $ 104,112 | ||
| Lease Cost | |||||
| Total | 4,165 | $ 3,575 | 12,781 | $ 12,026 | |
| Income Statement Location [Axis]: us-gaap:ResearchAndDevelopmentExpense | |||||
| Lease Cost | |||||
| Operating lease cost | 2,808 | 2,233 | 8,326 | 7,754 | |
| Variable lease cost | 620 | 893 | 2,710 | 2,830 | |
| Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense | |||||
| Lease Cost | |||||
| Operating lease cost | 737 | 449 | 1,745 | 1,442 | |
| Variable lease cost | $ 0 | $ 0 | $ 0 | $ 0 | |