Comprehensive Income or Loss - Income Tax Effects (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Foreign currency translation:
Net unrealized income tax benefit arising during the period	$ 8.7	$ 0.0	$ 8.7	$ 0.0
Derivative instruments:
Net unrealized income tax benefit (provision) arising during the period	0.0	0.2	(0.1)	0.5
Reclassification of net income tax (benefit) provision into earnings	0.0	(0.1)	0.1	(0.3)
Defined benefit plans:
Net unrealized income tax provision arising during the period	0.0	(2.4)	0.0	(2.4)
Reclassification of net income tax (benefit) provision into earnings	$ (0.3)	$ 2.6	$ (0.6)	$ 2.5