Restructuring - Restructuring Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Cumulative amount of restructuring costs	$ 76.2		$ 76.2	$ 71.0
Restructuring charges	2.2	$ 3.0	5.2
Restructuring Plan, 2018 | Severance and related expense
Restructuring Cost and Reserve [Line Items]
Cumulative amount of restructuring costs	27.7		27.7	25.4
Restructuring charges	0.1	2.2	2.3
Restructuring Plan, 2018 | Other
Restructuring Cost and Reserve [Line Items]
Cumulative amount of restructuring costs	46.2		46.2	45.6
Restructuring charges	0.5	0.1	0.6
Restructuring Plan, Other
Restructuring Cost and Reserve [Line Items]
Cumulative amount of restructuring costs	2.3		2.3
Restructuring Plan, Other | Other
Restructuring Cost and Reserve [Line Items]
Cumulative amount of restructuring costs	2.3		2.3	$ 0.0
Restructuring charges	$ 1.6	$ 0.7	$ 2.3