Financial Instruments - Effect of Derivative Instruments on Consolidated Statement of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 07, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative	$ 0.0	$ 0.7	$ (1.5)	$ (0.7)	$ (2.2)
Interest rate contracts | Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI Into Income	0.0	(0.8)	(0.1)	(1.3)	(0.1)
Make-whole derivative liability | Non-Operating Income (Expenses) – Net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives	0.0	(102.6)	0.0	(32.8)	0.0
Foreign exchange forward contracts | Non-Operating Income (Expenses) – Net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives	$ 1.8	$ (0.7)	$ (6.1)	$ (0.7)	$ (4.6)