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Retirement Plans (Tables) | 12 Months Ended
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Sep. 30, 2018
Defined Benefit Plan [Abstract] |
Schedule of Net Periodic Benefit Cost | During March 2017, the Financial Accounting Standards Board issued Accounting Standards Update No. 2017-07 (“ASU 2017-07”). ASU 2017-07 required us to exclude from operating income the components of net periodic benefit cost other than service cost. We adopted ASU 2017-07 on October 1, 2017, and this adoption required reclassification of pension costs other than service in the 2017 and 2016 results, which has the effect of increasing operating income by those amounts. The components of net periodic benefit cost for our Pension Plans are presented below.
| 2018 |  | 2017 |  | 2016
| (in millions)
Service cost | $ | 1.8 |  |  | $ | 2.0 |  |  | $ | 1.7 |
Components of net periodic benefit cost excluded from operating income following adoption of ASU 2017-07: |  |  |  |  |
Interest cost | 14.3 |  |  | 14.3 |  |  | 18.9 |
Expected return on plan assets | (16.5 | ) |  | (16.9 | ) |  | (19.7 | )
Amortization of actuarial net loss | 3.2 |  |  | 4.0 |  |  | 3.4 |
Pension settlement | — |  |  | — |  |  | 16.6 |
Other | — |  |  | — |  |  | 0.1 |
Pension costs other than service | 1.0 |  |  | 1.4 |  |  | 19.3 |
Net periodic benefit cost | $ | 2.8 |  |  | $ | 3.4 |  |  | $ | 21.0 |
Schedule of Accumulated and Projected Benefit Obligations | Balance sheet information for Pension Plans with accumulated benefit obligations in excess of plan assets is presented below.
| September 30,
| 2018 |  | 2017
| (in millions)
Projected benefit obligations | $ | 6.2 |  |  | $ | 379.5 |
Accumulated benefit obligations | 6.2 |  |  | 379.5 |
Fair value of plan assets | 5.0 |  |  | 364.2 |
Balance sheet information for Pension Plans with accumulated benefit obligations less than plan assets is presented below.
| September 30,
| 2018 |  | 2017
| (in millions)
Projected benefit obligations | $ | 327.1 |  |  | $ | 1.0 |
Accumulated benefit obligations | 327.1 |  |  | 1.0 |
Fair value of plan assets | 338.5 |  |  | 2.1 |
Schedule Of Defined Benefit Plans Disclosures | Amounts recognized for Pension Plans are presented below.
| Pension Plans
| 2018 |  | 2017
| (in millions)
Projected benefit obligations: |  |  |
Beginning of year | $ | 380.5 |  |  | $ | 403.1 |
Service cost | 1.8 |  |  | 2.0 |
Interest cost | 14.3 |  |  | 14.3 |
Actuarial gain | (38.6 | ) |  | (14.5 | )
Benefits paid | (24.3 | ) |  | (24.8 | )
Currency translation | (0.3 | ) |  | 0.4 |
Decrease in obligation due to curtailment / settlement | — |  |  | — |
End of year | $ | 333.4 |  |  | $ | 380.5 |
Accumulated benefit obligations at end of year | $ | 333.4 |  |  | $ | 380.5 |
Plan assets: |  |  |
Beginning of year | $ | 366.3 |  |  | $ | 340.0 |
Actual return on plan assets | 2.0 |  |  | 15.8 |
Employer contributions | — |  |  | 35.0 |
Currency translation | (0.3 | ) |  | 0.4 |
Benefits paid | (24.3 | ) |  | (24.8 | )
Other | (0.2 | ) |  | (0.1 | )
End of year | $ | 343.5 |  |  | $ | 366.3 |
Accrued benefit cost at end of year: |  |  |
Funded (unfunded) status | $ | 10.1 |  |  | $ | (14.2 | )
Recognized on balance sheet: |  |  |
Other noncurrent assets | $ | 11.2 |  |  | $ | 1.1 |
Other current liabilities | (1.1 | ) |  | (1.1 | )
Other noncurrent liabilities | — |  |  | (14.2 | )
| $ | 10.1 |  |  | $ | (14.2 | )
Recognized in accumulated other comprehensive loss, before tax: |  |  |
Prior year service cost | $ | — |  |  | $ | — |
Net actuarial loss | 66.0 |  |  | 93.4 |
| $ | 66.0 |  |  | $ | 93.4 |
Schedule of Pension and Other Postretirement Benefits Activity in Accumulated Other Comprehensive Income (Loss) [Table Text Block] | Pension Plan activity in accumulated other comprehensive loss, before tax, in 2018 is presented below, in millions.
Balance at beginning of year | $ | 93.4 |
Actuarial gain | (24.2 | )
Prior year actuarial loss amortization to net periodic cost | (3.2 | )
Balance at end of year | $ | 66.0 |
Schedule of Assumptions Used | A summary of key assumptions for our Pension Plans is below.
| Pension Plans
| 2018 |  | 2017 |  | 2016
Weighted average used to determine benefit obligations: |  |  |  |  |
Discount rate | 4.37 | % |  | 3.88 | % |  | 3.68 | %
Weighted average used to determine net periodic cost: |  |  |  |  |
Discount rate | 3.88 | % |  | 3.68 | % |  | 3.92 | %
Expected return on plan assets | 4.68 | % |  | 5.16 | % |  | 5.50 | %
Schedule of Strategic Allocation of Plan Assets [Table Text Block] | This trust’s strategic asset allocations, tactical range at September 30, 2018 and actual asset allocations are presented below.
| Strategic asset allocation |  |  |  |  |  |  | Actual asset allocations at
|  |  |  |  |  |  | September 30,
| Tactical range |  | 2018 |  | 2017 |  | 2016
Fixed income investments | 80 | % |  | 75 |  | 80 | % |  |  | 77 | % |  | 78 | % |  | 69 | %
Equity investments | 20 |  |  | 15 | - | 20 | % |  |  | 21 |  |  | 21 |  |  | 29 |
Cash | — |  |  | 0 | - | 5 | % |  |  | 2 |  |  | 1 |  |  | 2 |
| 100 | % |  |  |  |  |  |  | 100 | % |  | 100 | % |  | 100 | %
Schedule of Allocation of Plan Assets | The assets of the Pension Plans by level within the fair value hierarchy are presented below.
| September 30, 2018
| Level 1 |  | Level 2 |  | Total
| (in millions)
Fixed income | $ | — |  |  | $ | 264.1 |  |  | $ | 264.1 |
Equity: |  |  |  |  |
Large cap stocks: |  |  |  |  |
Large cap index funds | — |  |  | 30.5 |  |  | 30.5 |
Mid cap stocks: |  |  |  |  |
Mid cap index funds | — |  |  | 10.1 |  |  | 10.1 |
Small cap stocks: |  |  |  |  |
Small cap growth funds | — |  |  | 10.0 |  |  | 10.0 |
International stocks: |  |  |  |  |
Mutual funds | 11.8 |  |  | — |  |  | 11.8 |
International funds | — |  |  | 10.3 |  |  | 10.3 |
Total equity | 11.8 |  |  | 60.9 |  |  | 72.7 |
Cash and cash equivalents | 6.6 |  |  | — |  |  | 6.6 |
| $ | 18.4 |  |  | $ | 325.0 |  |  | $ | 343.4 |
| September 30, 2017
| Level 1 |  | Level 2 |  | Total
| (in millions)
Fixed income | $ | — |  |  | $ | 284.4 |  |  | $ | 284.4 |
Equity: |  |  |  |  |
Large cap stocks: |  |  |  |  |
Large cap growth funds | $ | — |  |  | $ | 32.6 |  |  | $ | 32.6 |
Mid cap stocks: |  |  |  |  |
Mid cap index funds | — |  |  | 10.9 |  |  | 10.9 |
Small cap stocks: |  |  |  |  |
Small cap growth funds | — |  |  | 11.3 |  |  | 11.3 |
International stocks: |  |  |  |  |
Mutual funds | 15.4 |  |  | — |  |  | 15.4 |
International funds | — |  |  | 7.4 |  |  | 7.4 |
Total equity | 15.4 |  |  | 62.2 |  |  | 77.6 |
Cash and cash equivalents | 4.3 |  |  | — |  |  | 4.3 |
| $ | 19.7 |  |  | $ | 346.6 |  |  | $ | 366.3 |
Schedule of Expected Benefit Payments | Our estimated future pension benefit payments are presented below in millions.
2019 | $ | 31.2 |
2020 | 25.0 |
2021 | 24.8 |
2022 | 24.5 |
2023 | 24.2 |
2024-2028 | 113.6 |

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