Income Taxes - Income (Loss) Before Income Taxes and Noncontrolling Interest (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Federal	[1]	$ (1.6)	$ (24.6)	$ (34.1)
International	[2]	409.1	404.4	206.9
Income from continuing operations before income taxes		$ 407.5	$ 379.8	$ 172.8
Federal statutory income tax rate		19.00%	19.00%	19.30%

[1] ⁽¹⁾  “Federal” reflects United Kingdom (“U.K.”) loss from continuing operations before income taxes.

[2] ⁽²⁾  “International” reflects non-U.K. income from continuing operations before income taxes.