Hedging Activities and Fair Value Measurements - Fair Value Measurements (Details) - Recurring - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Financial Assets
Foreign currency forwards	$ 3.3	$ 0.5
Trading securities held in deferred compensation plan	7.7	7.3
Total	11.0	7.8
Financial Liabilities
Foreign currency forwards	0.6	0.5
Deferred compensation plans	20.9	7.3
Interest rate swaps		13.1
Total	21.5	20.9
Level 1
Financial Assets
Foreign currency forwards	0.0	0.0
Trading securities held in deferred compensation plan	7.7	7.3
Total	7.7	7.3
Financial Liabilities
Foreign currency forwards	0.0	0.0
Deferred compensation plans	20.9	7.3
Interest rate swaps		0.0
Total	20.9	7.3
Level 2
Financial Assets
Foreign currency forwards	3.3	0.5
Trading securities held in deferred compensation plan	0.0	0.0
Total	3.3	0.5
Financial Liabilities
Foreign currency forwards	0.6	0.5
Deferred compensation plans	0.0	0.0
Interest rate swaps		13.1
Total	0.6	13.6
Level 3
Financial Assets
Foreign currency forwards	0.0	0.0
Trading securities held in deferred compensation plan	0.0	0.0
Total	0.0	0.0
Financial Liabilities
Foreign currency forwards	0.0	0.0
Deferred compensation plans	0.0	0.0
Interest rate swaps		0.0
Total	$ 0.0	$ 0.0