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v3.25.3

Retirement Plans (Tables) | 12 Months Ended
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Sep. 30, 2025
Retirement Benefits [Abstract] |
Schedule of Net Periodic Benefit Cost | The components of net periodic cost for the Pension Plan are presented below:
| 2025 |  | 2024 |  | 2023 |  |  |  |
| (in millions)
Service cost | $ | 0.7 |  |  | $ | 0.6 |  |  | $ | 0.8 |  |  |  |  |
Components of net periodic cost excluded from operating income: |  |  |  |  |  |  |  |  |
Interest cost | 12.0 |  |  | 13.9 |  |  | 13.9 |  |  |  |  |
Expected return on plan assets | (14.4) |  |  | (13.0) |  |  | (13.9) |  |  |  |  |
Amortization of actuarial net loss | 2.2 |  |  | 3.1 |  |  | 3.7 |  |  |  |  |
Pension (benefit) expense other than service | (0.2) |  |  | 4.0 |  |  | 3.7 |  |  |  |  |
Net periodic cost | $ | 0.5 |  |  | $ | 4.6 |  |  | $ | 4.5 |  |  |  |  |
Schedule Of Defined Benefit Plans Disclosures | Amounts recognized for the Pension Plan are presented below:
| September 30,
| 2025 |  | 2024
| (in millions)
Projected benefit obligations: |  |  |
Beginning of year | $ | 247.9 |  |  | $ | 233.2 |
Service cost | 0.7 |  |  | 0.6 |
Interest cost | 12.0 |  |  | 13.9 |
Actuarial (gain)/loss | (7.7) |  |  | 22.2 |
Benefits paid | (21.5) |  |  | (22.0) |
Accumulated benefit obligations at end of year | $ | 231.4 |  |  | $ | 247.9 |
Plan assets: |  |  |
Beginning of year | $ | 261.4 |  |  | $ | 239.8 |
Actual return on plan assets | 11.0 |  |  | 43.6 |
Benefits paid | (21.5) |  |  | (22.0) |
Fair value of plan assets at end of year | $ | 250.9 |  |  | $ | 261.4 |
Prepaid benefit cost at end of year: |  |  |
Funded status | $ | 19.5 |  |  | $ | 13.5 |
Recognized on balance sheet: |  |  |
Other noncurrent assets | $ | 19.5 |  |  | $ | 13.5 |
Recognized in accumulated other comprehensive loss, before tax: |  |  |
Net actuarial loss | $ | 50.2 |  |  | $ | 56.6 |
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 2025 is presented below (in millions):
Balance at beginning of year | $ | 56.6 |
Actuarial gain | (4.2) |
Prior year actuarial loss amortization to net periodic cost | (2.2) |
Balance at end of year | $ | 50.2 |
Schedule of Assumptions Used | A summary of key assumptions for the valuations of the Pension Plan is as follows:
| September 30,
| 2025 |  | 2024 |  | 2023
Weighted average used to determine benefit obligations: |  |  |  |  |
Discount rate | 5.47 | % |  | 5.07 | % |  | 6.29 | %
Weighted average used to determine net periodic cost: |  |  |  |  |
Discount rate | 5.07 | % |  | 6.29 | % |  | 5.79 | %
Expected return on plan assets | 5.75 | % |  | 5.75 | % |  | 5.75 | %
Schedule of Strategic Allocation of Plan Assets [Table Text Block] | Strategic asset allocations, tactical range as of September 30, 2025 and actual asset allocations are as follows:
| Strategic asset allocation |  |  |  |  |  | Actual asset allocations at
|  |  |  |  |  | September 30,
|  | Tactical range |  | 2025 |  | 2024 |  | 2023
Fixed income investments | 70 | % |  | 67 | % | - | 73 | % |  | 69 | % |  | 69 | % |  | 70 | %
Equity investments | 30 |  |  | 27 | % | - | 33 | % |  | 30 |  |  | 30 |  |  | 29 |
Cash | — |  |  | 0 | % | - | 5 | % |  | 1 |  |  | 1 |  |  | 1 |
| 100 | % |  |  |  |  |  | 100 | % |  | 100 | % |  | 100 | %
Schedule of Allocation of Plan Assets | The assets of the Pension Plan by level within the fair value hierarchy are as follows:
| September 30, 2025
| Level 1 |  | Level 2 |  |  |  | Total
| (in millions)
Fixed income | $ | 131.2 |  |  | $ | 41.9 |  |  |  |  | $ | 173.1 |
Equity: |  |  |  |  |  |  |
Large cap index funds | 38.0 |  |  | — |  |  |  |  | 38.0 |
International stocks: |  |  |  |  |  |  |
International funds | 37.7 |  |  | — |  |  |  |  | 37.7 |
Total equity | 75.7 |  |  | — |  |  |  |  | 75.7 |
Cash and cash equivalents | 2.1 |  |  | — |  |  |  |  | 2.1 |
Total Plan assets | $ | 209.0 |  |  | $ | 41.9 |  |  |  |  | $ | 250.9 |
| September 30, 2024
| Level 1 |  | Level 2 |  |  |  | Total
| (in millions)
Fixed income | $ | 131.8 |  |  | $ | 49.8 |  |  |  |  | $ | 181.6 |
Equity: |  |  |  |  |  |  |
Large cap index funds | 39.1 |  |  | — |  |  |  |  | 39.1 |
International stocks: |  |  |  |  |  |  |
International funds | 38.9 |  |  | — |  |  |  |  | 38.9 |
Total equity | 78.0 |  |  | — |  |  |  |  | 78.0 |
Cash and cash equivalents | 1.8 |  |  | — |  |  |  |  | 1.8 |
Total Plan assets | $ | 211.6 |  |  | $ | 49.8 |  |  |  |  | $ | 261.4 |
Schedule of Expected Benefit Payments | Our estimated future pension benefit payments as of September 30, 2025 are presented below (in millions):
2026 | $ | 22.3 |
2027 | 22.0 |
2028 | 21.5 |
2029 | 20.9 |
2030 | 20.3 |
2031-2035 | 90.7 |
Total | $ | 197.7 |

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- Definition Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + 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/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 20 -Topic 715 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-4 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-2 + Details
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- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (f) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (q) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (h) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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