Debt - Short-Term Borrowings (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Line of Credit Facility [Line Items]
Short-term borrowings	$ 186.5		$ 186.5		$ 235.0
Interest expense, net	1.9	$ 1.7	3.7	$ 3.1
Revolving Credit Facility
Line of Credit Facility [Line Items]
Short-term borrowings	186.5		186.5		$ 235.0
Minimum
Line of Credit Facility [Line Items]
Short-term borrowings	120.0	140.0	120.0	140.0
Maximum
Line of Credit Facility [Line Items]
Short-term borrowings	$ 257.0	$ 242.0	$ 257.0	$ 242.0