Other Income, Net - Schedule of Components of Other Income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Securities earnings:
Dividends and interest	$ 26.1	$ 29.4	$ 26.7
Securities transactions, net	12.4	0.1	0.5
Total	38.5	29.5	27.2
Gain on land sales	12.5
Insurance recoveries	1.3	0.4	0.4
Currency transactions, net	10.1	(7.5)	5.5
Disposal of property and equipment, net	(0.3)	(0.5)	(0.3)
Business interruption insurance proceeds			4.3
Infrastructure reimbursement	4.3	1.0	0.6
Other, net	2.8	2.3	1.3
Total	$ 69.2	$ 25.2	$ 39.0