Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Tax Note Textuals [Line Items]
Unrecognized Tax Benefits Impact on Effective Tax Rate	$ (13.4)
Tax Matters Agreement Receivable, Continuing Operations		$ 1.6
Tax Matters Agreement Receivable, Discontinued Operations		13.2
Additional deferred tax liability	12.7
Deferred taxes not provided for excess of financial reporting over tax basis of investments in foreign subsidiaries	671.6
Cash and Cash Equivalents	460.7	415.7	$ 584.0	$ 507.3
Net operating loss carryforwards in Luxembourg	152.1
Excess Tax benefit from stock activity	$ 3.2	3.4	10.4
The tax benefits recognized in the Consolidated Financial Statements from such positions are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement	The tax benefits recognized in the Consolidated Financial Statements from such positions are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement.
Estimated change in unrecognized tax benefits	$ 16.0
Interest (income) expense related to tax matters	(2.9)	(5.7)	0.8
Interest accrued from income tax examinations	6.8	9.8	$ 19.4
Tax Matters Agreement Receivable, Total		14.8
Tax Matters Agreement, Collection	1.5
Continuing Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		18.0
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	27.0
Discontinued Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		20.9
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	3.1
Non US Subsidiaries [Member]
Tax Note Textuals [Line Items]
Cash and Cash Equivalents	$ 435.5
Tax Benefit from Audit Adjustments [Member] | Continuing Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		8.0
Tax Benefit from Audit Adjustments [Member] | Discontinued Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		17.4
Recognition of Previously Unrecognized Tax Position [Member] | Continuing Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		10.0
Recognition of Previously Unrecognized Tax Position [Member] | Discontinued Operations [Member]
Tax Note Textuals [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions		$ 38.3