Other Operating Expenses (Income), net - Other Operating Expenses (Income), Net (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other Income and Expenses [Abstract]
Net losses (gains) on disposal of assets, restaurant closures, and refranchisings	$ 8.6	$ 1.0	$ 11.5	$ 16.3
Litigation settlements and reserves, net	1.1	0.9	1.1	1.6
Net losses (gains) on foreign exchange	36.8	(12.1)	47.2	12.0
Other, net	0.3	(1.1)	0.8	(0.4)
Other operating expenses (income), net	$ 46.8	$ (11.3)	$ 60.6	$ 29.5