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Retirement Plans (Tables) | 12 Months Ended
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Sep. 30, 2017
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”). This amendment to GAAP will require us to exclude from operating income the components of net periodic benefit cost other than service cost. We adopted this amendment on October 1, 2017, and this adoption will require reclassification of amounts included in 2017 and 2016 results. The components of net periodic benefit cost for our Pension Plans and the effects this adoption will have on operating income are presented below.
| 2017 |  | 2016 |  | 2015
| (in millions)
Service cost | $ | 2.0 |  |  | $ | 1.7 |  |  | $ | 1.9 |
Components of net periodic benefit cost that will be excluded from operating income upon adoption of ASU 2017-07: |  |  |  |  |
Interest cost | 14.3 |  |  | 18.9 |  |  | 20.1 |
Expected return on plan assets | (16.9 | ) |  | (19.7 | ) |  | (24.6 | )
Amortization of actuarial net loss | 4.0 |  |  | 3.4 |  |  | 3.2 |
Pension settlement | — |  |  | 16.6 |  |  | 0.5 |
Other | — |  |  | 0.1 |  |  | — |
| 1.4 |  |  | 19.3 |  |  | (0.8 | )
Net periodic benefit cost | $ | 3.4 |  |  | $ | 21.0 |  |  | $ | 1.1 |
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,
| 2017 |  | 2016
| (in millions)
Projected benefit obligations | $ | 379.5 |  |  | $ | 402.0 |
Accumulated benefit obligations | 379.5 |  |  | 402.0 |
Fair value of plan assets | 364.2 |  |  | 337.9 |
Balance sheet information for Pension Plans with accumulated benefit obligations less than plan assets is presented below.
| September 30,
| 2017 |  | 2016
| (in millions)
Projected benefit obligations | $ | 1.0 |  |  | $ | 1.1 |
Accumulated benefit obligations | 1.0 |  |  | 1.1 |
Fair value of plan assets | 2.1 |  |  | 2.1 |
Schedule Of Defined Benefit Plans Disclosures | Amounts recognized for Pension Plans and other postretirement benefit plans are presented below.
| Pension Plans
| 2017 |  | 2016
| (in millions)
Projected benefit obligations: |  |  |
Beginning of year | $ | 403.1 |  |  | $ | 428.2 |
Service cost | 2.0 |  |  | 1.7 |
Interest cost | 14.3 |  |  | 18.9 |
Actuarial loss (gain) | (14.5 | ) |  | 37.7 |
Benefits paid | (24.8 | ) |  | (25.1 | )
Currency translation | 0.4 |  |  | 0.2 |
Decrease in obligation due to curtailment / settlement | — |  |  | (58.5 | )
End of year | $ | 380.5 |  |  | $ | 403.1 |
Accumulated benefit obligations at end of year | $ | 380.5 |  |  | $ | 403.1 |
Plan assets: |  |  |
Beginning of year | $ | 340.0 |  |  | $ | 383.4 |
Actual return on plan assets | 15.8 |  |  | 40.1 |
Employer contributions | 35.0 |  |  | — |
Settlement | — |  |  | (58.5 | )
Currency translation | 0.4 |  |  | 0.1 |
Benefits paid | (24.8 | ) |  | (25.1 | )
Other | (0.1 | ) |  | — |
End of year | $ | 366.3 |  |  | $ | 340.0 |
Accrued benefit cost at end of year: |  |  |
Unfunded status | $ | (14.2 | ) |  | $ | (63.1 | )
Recognized on balance sheet: |  |  |
Other noncurrent assets | $ | 1.1 |  |  | $ | 1.0 |
Other current liabilities | (1.1 | ) |  | (1.2 | )
Other noncurrent liabilities | (14.2 | ) |  | (62.9 | )
| $ | (14.2 | ) |  | $ | (63.1 | )
Recognized in accumulated other comprehensive loss, before tax: |  |  |
Prior year service cost | $ | — |  |  | $ | — |
Net actuarial loss | 93.4 |  |  | 110.8 |
| $ | 93.4 |  |  | $ | 110.8 |
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 2017 is presented below, in millions.
Balance at beginning of year | $ | 110.8 |
Actuarial loss | (13.5 | )
Prior year actuarial loss amortization to net periodic cost | (4.0 | )
Other | 0.1 |
Balance at end of year | $ | 93.4 |
Schedule of Components of Accumulated Other Comprehensive Income (Loss) Related to Pension and Other Postretirement Benefits Expected to be Amortized | The components of accumulated other comprehensive loss related to Pension Plans that we expect to amortize into net periodic benefit cost in 2018 are presented below, in millions.
Amortization of unrecognized prior year service cost | $ | — |
Amortization of unrecognized loss | 3.2 |
| $ | 3.2 |
Schedule of Assumptions Used | A summary of key assumptions for our pension plans is below.
| Pension Plans
| 2017 |  | 2016 |  | 2015
Weighted average used to determine benefit obligations: |  |  |  |  |
Discount rate | 3.88 | % |  | 3.68 | % |  | 4.84 | %
Weighted average used to determine net periodic cost: |  |  |  |  |
Discount rate | 3.68 | % |  | 3.92 | % |  | 4.49 | %
Expected return on plan assets | 5.16 |  |  | 5.50 |  |  | 6.21 |
Schedule of Strategic Allocation of Plan Assets [Table Text Block] | his trust’s strategic asset allocations, tactical range at September 30, 2017 and actual asset allocations are presented below.
| Strategic asset allocation |  |  |  |  |  |  | Actual asset allocations at
|  |  |  |  |  |  | September 30,
| Tactical range |  | 2017 |  | 2016 |  | 2015
Equity investments: |  |  |  |  |  |  |  |  |  |  |  |
Large capitalization stocks | 12 | % |  |  |  |  |  |  |  |  |  |  |
Small capitalization stocks | 3 |  |  |  |  |  |  |  |  |  |  |  |
International stocks | 5 |  |  |  |  |  |  |  |  |  |  |  |
| 20 |  |  | 15 | - | 20 | % |  |  | 21 | % |  | 29 | % |  | 39 | %
Fixed income investments | 80 |  |  |  |  | 80 |  |  |  | 78 |  |  | 69 |  |  | 60 |
Cash | — |  |  | 0 | - | 5 |  |  |  | 1 |  |  | 2 |  |  | 1 |
| 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, 2017
| Level 1 |  | Level 2 |  | Total
| (in millions)
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 |
Fixed income | — |  |  | 284.4 |  |  | 284.4 |
Cash and cash equivalents | 4.3 |  |  | — |  |  | 4.3 |
| $ | 19.7 |  |  | $ | 346.6 |  |  | $ | 366.3 |
| September 30, 2016
| Level 1 |  | Level 2 |  | Total
| (in millions)
Equity: |  |  |  |  |
Large cap stocks: |  |  |  |  |
Large cap growth funds | $ | — |  |  | $ | 7.3 |  |  | $ | 7.3 |
Large cap index funds | — |  |  | 38.2 |  |  | 38.2 |
Large cap value funds | — |  |  | 7.2 |  |  | 7.2 |
Small cap stocks: |  |  |  |  |
Small cap growth funds | — |  |  | 15.1 |  |  | 15.1 |
International stocks: |  |  |  |  |
Mutual funds | 13.5 |  |  | — |  |  | 13.5 |
International funds | — |  |  | 18.1 |  |  | 18.1 |
Total equity | 13.5 |  |  | 85.9 |  |  | 99.4 |
Fixed income | — |  |  | 233.3 |  |  | 233.3 |
Cash and cash equivalents | 7.3 |  |  | — |  |  | 7.3 |
| $ | 20.8 |  |  | $ | 319.2 |  |  | $ | 340.0 |
Schedule of Expected Benefit Payments | Our estimated future pension benefit payments are presented below in millions.
2018 | $ | 32.1 |
2019 | 25.4 |
2020 | 25.4 |
2021 | 25.2 |
2022 | 25.0 |
2023-2027 | 120.1 |

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- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the amounts related to pension plans and/or other employee benefit plans in accumulated other comprehensive income (loss) expected to be recognized as components of net periodic benefit cost over the next fiscal year, including the net gain (loss), net prior service cost or credit, and net transition asset or obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the assumptions used to determine for pension plans and/or other employee benefit plans the benefit obligation and net benefit cost, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2439-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2410-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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