Fair Value of Financial Instruments - Financial assets and liabilities accounted for at fair value on a recurring basis by level within the fair value hierarchy (Details) - Estimate of Fair Value Measurement - Fair Value, Measurements, Recurring - Foreign Currency Exchange Contracts $ in Millions	Dec. 31, 2018 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivatives assets, current	$ 0.1
Derivative liabilities, current	1.8
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivatives assets, current	0.1
Derivative liabilities, current	$ 1.8