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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Income Tax Disclosure [Abstract] |  |  |
Operating loss carryforwards | $ 13.0 | $ 5.3 |
State and local net operating loss carryforwards of net of valuation allowance | 12.1 |  |
Federal operating loss carryforwards, net of valuation allowances | 0.6 |  |
Foreign operating loss carryforwards, net of valuation allowances | 0.3 |  |
Valuation allowance | 18.5 | 15.5 |
Increase in total valuation allowance | 3.0 |  |
Foreign earnings repatriated | 73.5 | 100.0 |
Unrecognized tax benefits that would impact effective tax rate | 0.5 | 0.0 | $ 0.0
Unrecognized tax benefits, income tax penalties and interest accrued | 0.1 | 0.1 |
Income tax examination, penalties and interest expense | $ 0.0 | $ 0.1 | $ 0.0

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- Definition Deferred Tax Assets, Net of Valuation Allowance, Operating Loss Carryforwards, State and Local - Amount after allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. + References No definition available. + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
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- Definition The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15 + Details
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 217 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-217 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15 + Details
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