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Leases - Balance Sheet Information (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Sep. 30, 2024
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Leases [Abstract] |  |
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Other noncurrent assets | Other noncurrent assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other current liabilities | Other current liabilities
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Other noncurrent liabilities | Other noncurrent liabilities
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Current portion of long-term debt | Current portion of long-term debt
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Long-term debt | Long-term debt
Operating lease right-of-use assets | $ 27.3 | $ 26.9
Finance Lease, Right-of-Use Asset, after Accumulated Amortization | 4.1 | 2.7
Total Right of Use Assets | 31.4 | 29.6
Operating lease liability | 6.4 | 5.5
Operating Lease, Liability, Noncurrent | 22.0 | 22.5
Finance Lease Liability, Current | 1.2 | 0.8
Finance Lease, Liability, Noncurrent | 2.9 | 1.9
Total Lease Liabilities | $ 32.5 | $ 30.7

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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479041/842-20-45-1 + Details
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