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Supplemental Statement of Operations Information (Tables) | 12 Months Ended
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Sep. 30, 2025
Other Income and Expenses [Abstract] |
Restructuring and Related Costs | Activity in accrued restructuring, reported within Other current liabilities, is presented below:
| 2025 |  | 2024 |  | 2023
| (in millions)
Balance at beginning of year | $ | 3.4 |  |  | $ | 6.6 |  |  | $ | 3.3 |
Expenses incurred | 8.8 |  |  | 15.8 |  |  | 10.2 |
Amounts paid and other adjustments, net | (11.1) |  |  | (19.0) |  |  | (6.9) |
Balance at end of year | $ | 1.1 |  |  | $ | 3.4 |  |  | $ | 6.6 |
Selected Supplemental Statement of Operations Information | Selected supplemental statement of operations information is presented below:
| 2025 |  | 2024 |  | 2023
| (in millions)
Included in selling, general and administrative expenses: |  |  |  |  |
Research and development | $ | 19.9 |  |  | $ | 20.5 |  |  | $ | 25.9 |
Advertising | $ | 4.6 |  |  | $ | 5.8 |  |  | $ | 4.7 |
Interest expense, net: |  |  |  |  |
4.0% Senior Notes | $ | 18.0 |  |  | $ | 18.0 |  |  | $ | 18.0 |
Deferred financing costs amortization | 1.0 |  |  | 1.0 |  |  | 1.0 |
ABL Agreement | 0.8 |  |  | 0.9 |  |  | 0.9 |
Capitalized interest | (0.5) |  |  | (0.1) |  |  | (1.6) |
Other interest expense | 0.7 |  |  | 1.7 |  |  | 0.1 |
Total interest expense | 20.0 |  |  | 21.5 |  |  | 18.4 |
Interest income | (13.4) |  |  | (8.8) |  |  | (3.7) |
Net interest expense | $ | 6.6 |  |  | $ | 12.7 |  |  | $ | 14.7 |

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- Definition Tabular disclosure of costs incurred for restructuring including, but not limited to, exit and disposal activities, remediation, implementation, integration, asset impairment, and charges against earnings from the write-down of assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.P.3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479823/420-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482017/420-10-50-1 + Details
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