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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Income Tax Contingency [Line Items] |  |
Unrecognized tax benefits would impact effective tax rate if recognized | $ 16.4 |
Unrecognized tax benefit | $ 16.4 | $ 16.0
Income tax examination, description | The Company and its U.S. subsidiaries remain open to examination by the IRS for years 2017 onwards under the statute of limitations. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including Germany (2016 onwards), Switzerland (2016 onwards), Spain (2017 onwards), France (2018 onwards) and the United Kingdom (2018 onwards |
Increase to income tax expense | $ 0.5 |
Foreign Exchange Movements | 0.2 |
Italian Tax Authorities [Member] |  |
Income Tax Contingency [Line Items] |  |
Unrecognized tax benefit | 3.3 |
Italian Tax Authorities [Member] | Interest Accrued [Member] |  |
Income Tax Contingency [Line Items] |  |
Increase to income tax expense | 0.1 |
Historical Impairment Of Subsidiaries [Member] |  |
Income Tax Contingency [Line Items] |  |
Other Non Significant Items Inclusive Of Interest And Penalties | 0.2 |
United States [Member] |  |
Income Tax Contingency [Line Items] |  |
Unrecognized tax benefit | $ 12.9 |
Non-US [Member] | Earliest Tax Year [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2011 |
Non-US [Member] | Latest Tax Year [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2014 |

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