Financial Instruments - Effect of Derivative Instruments on Consolidated Statement of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 07, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative	$ 0.0	$ 0.8	$ 0.1	$ 0.1	$ (2.1)
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)	(0.2)	(2.1)	(0.3)
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	0.0	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	$ 3.1	$ (4.5)	$ 2.4	$ (9.1)