Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
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

Deferred Tax Assets, Net Of Valuation Allowance, Operating Loss Carryforwards, Federal

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- Definition

Deferred Tax Assets, Net Of Valuation Allowance, Operating Loss Carryforwards, Foreign

+ References

No definition available.

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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.

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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

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- Definition

Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

+ References

No definition available.

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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
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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
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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.

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-Topic 740
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

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-Name Accounting Standards Codification
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