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v3.23.3

Income Taxes - Gross Unrecognized (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2023 | Sep. 30, 2022
Reconciliation of the beginning and ending amount of gross unrecognized tax benefits |  |
Balance at the beginning of the year | $ 55.2 | $ 46.4
Gross increase in current period's tax positions | 3.5 | 17.4
Gross increase in prior years' tax positions | 17.9 | 2.4
Gross decrease in prior years' tax positions | (13.3) | (8.0)
Decrease due to settlement with tax authorities | (1.0) | (1.4)
Decrease due to lapse of statute of limitations |  | (0.5)
Gross change due to foreign exchange fluctuations | (0.2) | (1.1)
Balance at the end of the year | 62.1 | 55.2
Income Taxes, additional disclosures |  |
Accrued interest, excluding any related income tax benefits | 24.4 | 20.5
Accrued penalties, excluding any related income tax benefits | $ 1.5 | $ 1.7

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-15A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10B -Publisher FASB -URI https://asc.fasb.org//1943274/2147482525/740-10-45-10B + Details
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- Definition Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return. + 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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