Cost-Reduction Actions - Liabilities and Expected Future Payments Related to Work-Force Reduction Actions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Restructuring Reserve [Roll Forward]
Additional provisions	$ 0.8	$ 13.2	$ 14.4	$ 48.6
Work-force Reductions
Restructuring Reserve [Roll Forward]
Balance at beginning of period			55.9
Additional provisions			6.5
Payments			(31.8)
Changes in estimates			(9.0)
Translation adjustments			(1.3)
Balance at end of period	20.3		20.3
Short-term	17.1		17.1
Long-term	3.2		3.2
Work-force Reductions | U.S.
Restructuring Reserve [Roll Forward]
Balance at beginning of period			13.1
Additional provisions			4.0
Payments			(11.8)
Changes in estimates			(0.5)
Translation adjustments			0.0
Balance at end of period	4.8		4.8
Short-term	4.8		4.8
Long-term	0.0		0.0
Work-force Reductions | International
Restructuring Reserve [Roll Forward]
Balance at beginning of period			42.8
Additional provisions			2.5
Payments			(20.0)
Changes in estimates			(8.5)
Translation adjustments			(1.3)
Balance at end of period	15.5		15.5
Short-term	12.3		12.3
Long-term	$ 3.2		$ 3.2