Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 4.4	$ 5.2	$ 4.5
State and local	1.1	1.3	2.1
Foreign	15.3	14.3	14.9
Total Current Income Tax	20.8	20.8	21.5
Deferred:
Federal	(0.7)	12.8	3.3
State and local	(0.3)	0.5	0.3
Foreign	2.0	(1.3)	1.7
Total Deferred Income Tax	1.0	12.0	5.3
Total	$ 21.8	$ 32.8	$ 26.8