Unaudited condensed consolidated statements of comprehensive income or loss - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 164.0	$ 47.0
Other comprehensive loss:
Foreign currency translation — unrealized loss	(33.5)	(68.8)
Derivative instruments:
Unrealized (loss) gain	(0.9)	1.6
Reclassification of loss (gain) into earnings	0.7	(0.1)
Defined benefit plans:
Unrealized gain	0.6	0.4
Reclassification of gain into earnings	0.0	(0.1)
Other comprehensive loss before income taxes	(33.1)	(67.0)
Income tax effect	(4.7)	(0.4)
Other comprehensive loss	(37.8)	(67.4)
Comprehensive income (loss)	$ 126.2	$ (20.4)