Fair Value of Financial Instruments - Reconciliation of Liabilities Measured at Fair Value Using Significant Unobservable Inputs Level 3 (Parenthetical) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Long-Term Credit Facility
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Cost	$ 426,456	$ 461,456	$ 212,420