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Retirement Plans (Tables) | 12 Months Ended
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Sep. 30, 2021
Retirement Benefits [Abstract] |
Schedule of Net Periodic Benefit Cost | The components of net periodic benefit cost for our Pension Plans are presented below.
| 2021 |  | 2020 |  | 2019 |  |  |  |
| (in millions)
Service cost | $ | 1.5 |  |  | $ | 1.5 |  |  | $ | 1.6 |  |  |  |  |
Components of net periodic cost (benefit) excluded from operating income: |  |  |  |  |  |  |  |  |
Interest cost | 9.9 |  |  | 11.2 |  |  | 13.9 |  |  |  |  |
Expected return on plan assets | (15.7) |  |  | (16.9) |  |  | (16.2) |  |  |  |  |
Amortization of actuarial net loss | 2.5 |  |  | 2.8 |  |  | 1.9 |  |  |  |  |
Pension settlement | — |  |  | — |  |  | 0.7 |  |  |  |  |
Other | — |  |  | (0.1) |  |  | 0.1 |  |  |  |  |
Pension (benefit) cost other than service | (3.3) |  |  | (3.0) |  |  | 0.4 |  |  |  |  |
Net periodic benefit (benefit) cost | $ | (1.8) |  |  | $ | (1.5) |  |  | $ | 2.0 |  |  |  |  |
Schedule of Accumulated and Projected Benefit Obligations | P
Schedule Of Defined Benefit Plans Disclosures | Amounts recognized for Pension Plans are presented below.
| 2021 |  | 2020
| (in millions)
Projected benefit obligations: |  |  |
Beginning of year | $ | 359.5 |  |  | $ | 356.6 |
Service cost | 1.5 |  |  | 1.5 |
Interest cost | 9.9 |  |  | 11.2 |
Actuarial gain | (10.8) |  |  | 13.7 |
Benefits paid | (23.3) |  |  | (23.5) |
End of year | $ | 336.8 |  |  | $ | 359.5 |
Accumulated benefit obligations at end of year | $ | 336.8 |  |  | $ | 359.5 |
Plan assets: |  |  |
Beginning of year | $ | 360.4 |  |  | $ | 351.6 |
Actual return on plan assets | 16.4 |  |  | 32.2 |
Employer contributions | — |  |  | 0.1 |
Benefits paid | (23.3) |  |  | (23.5) |
End of year | $ | 353.5 |  |  | $ | 360.4 |
Accrued benefit cost at end of year: |  |  |
Funded status | $ | 16.8 |  |  | $ | 0.9 |
Recognized on balance sheet: |  |  |
Other noncurrent assets | $ | 16.8 |  |  | $ | 0.9 |
Recognized in accumulated other comprehensive income (loss), before tax: |  |  |
Net actuarial loss | 59.9 |  |  | 74.0 |
| $ | 59.9 |  |  | $ | 74.0 |
Schedule of Pension and Other Postretirement Benefits Activity in Accumulated Other Comprehensive Income (Loss) [Table Text Block] | lan activity in accumulated other comprehensive loss, before tax, in 2021 is presented below, in millions.
Balance at beginning of year | $ | 74.0 |
Actuarial gain | (11.6) |
Prior year actuarial loss amortization to net periodic cost | (2.5) |
Balance at end of year | $ | 59.9 |
Schedule of Assumptions Used | A summary of key assumptions for the valuations of our Pension Plans is as follows
| 2021 |  | 2020 |  | 2019
Weighted average used to determine benefit obligations: |  |  |  |  |
Discount rate | 3.01 | % |  | 2.84 | % |  | 3.26 | %
Weighted average used to determine net periodic cost: |  |  |  |  |
Discount rate | 2.84 | % |  | 3.26 | % |  | 4.37 | %
Expected return on plan assets | 4.50 | % |  | 5.00 | % |  | 4.93 | %
Schedule of Strategic Allocation of Plan Assets [Table Text Block] | trategic asset allocations, tactical range at September 30, 2021 and actual asset allocations are as follows:
| Strategic asset allocation |  |  |  |  |  |  | Actual asset allocations at
|  |  |  |  |  |  | September 30,
|  | Tactical range |  | 2021 |  | 2020 |  | 2019
Fixed income investments | 70 | % |  | 65 |  | - | 70 | % |  |  | 70 | % |  | 78 | % |  | 79 | %
Equity investments | 30 |  |  | 25 |  | - | 30 | % |  |  | 29 |  |  | 21 |  |  | 19 |
Cash | — |  |  | 0 |  | - | 5 | % |  |  | 1 |  |  | 1 |  |  | 2 |
| 100 | % |  |  |  |  |  |  | 100 | % |  | 100 | % |  | 100 | %
Schedule of Allocation of Plan Assets | The assets of the Plan by level within the fair value hierarchy are as follows:
| September 30, 2021
| Level 1 |  | Level 2 |  |  |  | Total
| (in millions)
Fixed income | $ | 176.7 |  |  | $ | 70.3 |  |  |  |  | $ | 247.0 |
Equity: |  |  |  |  |  |  |
Large cap index funds | 52.1 |  |  | — |  |  |  |  | 52.1 |
International stocks: |  |  |  |  |  |  |
International funds | 52.5 |  |  | — |  |  |  |  | 52.5 |
Total equity | 104.6 |  |  | — |  |  |  |  | 104.6 |
Cash and cash equivalents | 1.9 |  |  | — |  |  |  |  | 1.9 |
| $ | 283.2 |  |  | $ | 70.3 |  |  |  |  | $ | 353.5 |
| September 30, 2020
| Level 1 |  | Level 2 |  |  |  | Total
| (in millions)
Fixed income | $ | — |  |  | $ | 280.3 |  |  |  |  | $ | 280.3 |
Equity: |  |  |  |  |  |  |
Large cap index funds | — |  |  | 32.8 |  |  |  |  | 32.8 |
Mid cap index funds | — |  |  | 13.5 |  |  |  |  | 13.5 |
Small cap growth funds | — |  |  | 12.7 |  |  |  |  | 12.7 |
International stocks: |  |  |  |  |  |  |
Mutual funds | 7.4 |  |  | — |  |  |  |  | 7.4 |
International funds | — |  |  | 10.4 |  |  |  |  | 10.4 |
Total equity | 7.4 |  |  | 69.4 |  |  |  |  | 76.8 |
Cash and cash equivalents | 3.3 |  |  | — |  |  |  |  | 3.3 |
| $ | 10.7 |  |  | $ | 349.7 |  |  |  |  | $ | 360.4 |
Schedule of Expected Benefit Payments | Our estimated future pension benefit payments are presented below (in millions).
2022 | $ | 24.1 |
2023 | 23.9 |
2024 | 23.5 |
2025 | 23.1 |
2026 | 22.7 |
2027-2031 | $ | 104.7 |

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