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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Unrecognized tax benefit	$ 14.2	$ 14.0
Income tax interest expense	0.2		$ 1.9
Uncertain tax positions	$ 0.2
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), France (2016 onwards), Germany (2014 onwards), Switzerland (2014 onwards) and the United Kingdom (2017 onwards).
Accrued net interest and penalties	$ 0.2	0.3
Unrecognized tax benefits, interest and penalties	14.2	14.0
Unrecognized tax benefits, income tax interest and penalties accrued	$ 0.8	0.6
Italian Tax Authorities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefit				$ 0.9	$ 0.5
Income tax interest expense				$ 0.3	$ 0.2
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
France [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2014
Germany [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2015
Switzerland [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2015
United Kingdom [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2016
United States [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2015

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