Employee Benefit Plans - Performance-Based Restricted Stock Units (Details) - Performance Shares - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Fiscal 2025 Grant
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	99,097
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 35.20
Share-Based Payment Arrangement, Expense		$ 1.2	$ 0.0	$ 0.0
Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		0.00%
Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		200.00%