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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Dec. 31, 2024 | Sep. 30, 2024 | Dec. 31, 2023
Income Tax Contingency [Line Items] |  |  |
Unrecognized tax benefits would impact effective tax rate if recognized |  | $ 11.0 |
Unrecognized tax benefit |  | 11.0 | $ 14.8
Increase to income tax expense |  | 0.8 |
Italian Tax Authorities [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Unrecognized tax benefit |  | 3.4 |
United Kingdom [Member] | Foreign [Member] | Profit Diversion Compliance Facility [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Income tax examination penalties and interest expenses |  | 1.2 |
United States [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Unrecognized tax benefit |  | $ 11.0 |
Non-US [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Open tax year |  | 2011 2012 2013 2014 |
Non-US [Member] | Historical Impairment Of Subsidiaries [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Decrease in uncertain tax positions | $ 11.0 |  |

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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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