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Stock-based Compensation Plans (Narrative) (Details) $ / shares in Units, $ in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Nov. 28, 2023 | Jun. 30, 2024 USD ($) $ / shares shares | Mar. 31, 2024 $ / shares shares | Dec. 31, 2023 $ / shares shares | Jun. 30, 2023 USD ($) shares | Jun. 30, 2024 USD ($) $ / shares shares | Jun. 30, 2023 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate | 2.00% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate | 4.50% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | 2 years 10 months 2 days |  |  |  |  |  |
Share-based Payment Arrangement, Expense | $ |  | $ 3.7 |  |  | $ 2.7 | $ 10.1 | $ 8.8
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ |  | $ 12.3 |  |  |  | $ 12.3 |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  | 24,636 |  |  | 249,933 | 520,420 | 1,156,428
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation |  | 249 |  |  |  | 120,162 |
Phantom Share Units (PSUs) [Member] |  |  |  |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  | $ 15.70 | $ 15.71 | $ 13.22 |  |  |
Granted, shares |  | 3,183 | 2,544 | 230,523 |  |  |
Share-based compensation liability | $ |  | $ 4.1 |  |  |  | $ 4.1 |
Share Based Compensation Arrangement By Share Based Payment Award, Fair Value | $ / shares |  | $ 17.92 |  |  |  | $ 17.92 |
Performance Shares [Member] |  |  |  |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  |  |  | $ 13.22 |  |  |
Granted, shares |  |  |  | 136,983 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period |  |  |  |  |  | 3 years |
Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture |  | 0 |  |  |  | 168,897 |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  | $ 18.44 | $ 15.59 | $ 13.27 |  |  |
Granted, shares |  | 55,572 | 81,136 | 161,943 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period |  |  |  |  |  | 3 years |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period |  | 696 |  |  |  | 260,110 |
Market Based Performance Shares |  |  |  |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  |  |  | $ 18.11 |  |  |
Granted, shares |  |  |  | 136,983 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period |  |  |  |  |  | 3 years |
Share-based Payment Arrangement, Option [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate | 1.94% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  |  |  | $ 3.96 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate | 4.33% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | 6 years |  |  |  |  |  |
Granted, shares |  |  |  | 457,356 |  |  |
Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture |  | 51,708 |  |  |  | 122,258 |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  |  | 3 years |
Employee Stock [Member] |  |  |  |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  | $ 3.01 | $ 2.62 | $ 3.48 |  |  |
Granted, shares |  | 31,659 | 35,998 | 31,139 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Discount from Market Price, Offering Date |  | 85.00% |  |  |  |  |
Minimum [Member] | Performance Shares [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Performance Factors |  |  |  |  |  | 0 |
Minimum [Member] | Market Based Performance Shares |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Performance Factors |  |  |  |  |  | 0 |
Maximum [Member] | Performance Shares [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Performance Factors |  |  |  |  |  | 2 |
Maximum [Member] | Market Based Performance Shares |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Performance Factors |  |  |  |  |  | 2 |

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