Other Income, Net - Schedule of Components of Other Income (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Securities earnings:
Dividends and interest			$ 13.6	$ 13.2
Securities transactions, net			0.1	0.2
Total	$ 6.9	$ 6.7	13.7	13.4
Currency transactions, net			4.2	1.3
Insurance recoveries	0.2	0.3	0.3	3.4
Business interruption insurance proceeds			3.4
Other, net			0.5	1.4
Total other income	$ 10.7	$ 7.4	$ 22.1	$ 19.5