Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Class of Stock [Line Items]
Equity Securities Registered, Value	$ 750.0
At-the-market Equity Offering Program, Common Stock Available for Issuance	300.0
Common Stock, Shares Authorized	750.0
Stock-based compensation expense	$ 3.1	$ 2.6
Performance Shares
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period	3 years
Restricted Stock Units (RSUs) \| Minimum
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period	3 years
Restricted Stock Units (RSUs) \| Maximum
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period	5 years
First Quarter Two Thousand Twenty Six Grant \| Performance Shares
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	114,565
Stock-based compensation expense	$ 0.2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 26.06
First Quarter Two Thousand Twenty Six Grant \| Performance Shares \| Minimum
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage	0.00%
First Quarter Two Thousand Twenty Six Grant \| Performance Shares \| Maximum
Class of Stock [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage	200.00%
First Quarter Two Thousand Twenty Six Grant \| Time-Based RSU
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	321,285
Stock-based compensation expense	$ 1.4
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 27.07
First Quarter Two Thousand Twenty Six Grant \| Time-Based RSU \| Retirement Eligible
Class of Stock [Line Items]
Stock-based compensation expense	$ 1.1

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