Restructuring Costs - Summary of Changes in Restructuring Reserve (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 22.2	$ 25.8
Expense	$ 71.7	$ 4.0	73.0	9.4
Paid/Utilized			(17.9)	(17.1)
Restructuring reserve, ending balance	77.3	18.1	77.3	18.1
Severance and benefits
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			21.6	24.6
Expense			70.7	8.3
Paid/Utilized			(15.6)	(15.8)
Restructuring reserve, ending balance	76.7	17.1	76.7	17.1
Plant closing and other
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			0.6	1.2
Expense			2.3	1.1
Paid/Utilized			(2.3)	(1.3)
Restructuring reserve, ending balance	$ 0.6	$ 1.0	$ 0.6	$ 1.0