The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Financial Instruments - (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Financial Instruments - (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Interest rate cap, fair value	$ 1.0		$ 1.0		$ 1.0
Unrealized (loss) gain from hedge accounting	0.0	$ 4.1	0.2	$ 12.4
Interest Rate Cap
Derivative [Line Items]
Notional amount	2,800.0		2,800.0		$ 2,800.0
Interest Rate Cap Agreement Maturity Date December 31, 2020
Derivative [Line Items]
Notional amount	1,400.0		1,400.0
Interest Rate Cap Agreement Maturity Date December 31, 2022
Derivative [Line Items]
Notional amount	1,400.0		1,400.0
Interest Rate Contract
Derivative [Line Items]
Unrealized (loss) gain from hedge accounting	0.0	(4.1)	(0.2)	(12.4)
Amount expected to be reclassified from AOCL to interest expense in next twelve months			6.0
Derivative
Derivative [Line Items]
Interest income (expense) reclassified into earnings	$ 1.4	$ 0.2	$ 2.5	$ 1.7