Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Recurring - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value
Recurring fair value measurements
Cash and cash equivalents	$ 12.5	$ 6.8
Derivative instruments - Liability position	(4.1)
Derivative instruments - Asset position		6.5
Total recurring fair value measurements	8.4	13.3
Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Recurring fair value measurements
Cash and cash equivalents	12.5	6.8
Derivative instruments - Liability position	0.0
Derivative instruments - Asset position		0.0
Total recurring fair value measurements	12.5	6.8
Fair Value | Significant Other Observable Inputs (Level 2)
Recurring fair value measurements
Cash and cash equivalents	0.0	0.0
Derivative instruments - Liability position	(4.1)
Derivative instruments - Asset position		6.5
Total recurring fair value measurements	(4.1)	6.5
Carrying Value
Recurring fair value measurements
Cash and cash equivalents	12.5	6.8
Derivative instruments - Liability position	(4.1)
Derivative instruments - Asset position		6.5
Total recurring fair value measurements	$ 8.4	$ 13.3