Income Taxes - Income Tax Data from Continuing Operations (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income components:
United States	$ (124.3)	$ 143.9	$ 114.4
International	209.5	270.5	276.6
Income from continuing operations before income tax	85.2	414.4	391.0
Current income tax expense:
United States – federal	9.9	9.4	6.3
United States – state and local	(1.5)	0.5	7.9
International	50.8	49.1	58.2
Total current income tax expense	59.2	59.0	72.4
Deferred income tax (benefit) expense components:
United States – federal	(36.6)	10.1	7.4
United States – state and local	(4.8)	1.5	(0.2)
International	(2.5)	19.3	(21.9)
Total deferred income tax (benefit) expense	(43.9)	30.9	(14.7)
Income tax expense	$ 15.3	$ 89.9	$ 57.7
Effective income tax rate	18.00%	21.70%	14.80%