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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2019
Income Tax Contingency [Line Items]
Unrecognized tax benefit	$ 14.0				$ 14.6
Income tax interest expense		$ 2.0			0.5
Uncertain tax positions					$ 0.6
Income tax examination, description					The Company and its U.S. subsidiaries remain open to examination by the IRS for years 2015 onwards under the statute of limitations. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including Spain (2014 onwards), Italy (2013 onwards), France (2016 onwards), Germany (2014 onwards), Switzerland (2014 onwards) and the United Kingdom (2017 onwards).
Accrued net interest and penalties	0.3				$ 0.6
Unrecognized tax benefits, interest and penalties	14.0				14.6
Unrecognized tax benefits, income tax interest and penalties accrued	0.6				1.2
Italian Tax Authorities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefit			$ 0.9	$ 0.5
Income tax interest expense			$ 0.3	$ 0.2	$ 0.1
Tax Cuts and Jobs Act [Member]
Income Tax Contingency [Line Items]
Uncertain tax positions	$ 10.8
Italy [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2011
Italy [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2013
SPAIN | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2014
France [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2016
Germany [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2014
Switzerland [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2014
United Kingdom [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year					2017

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