Fair Value Disclosure (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	$ 14.9	$ (11.8)	$ (7.4)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(20.4)	17.4	12.9
Other Nonoperating Income (Expense) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	12.8	(14.3)	(11.7)
Interest Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	2.1	2.5	4.2
Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Other Nonoperating Income (Expense) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(12.8)	14.3	11.7
Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Interest Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		0.0	0.0
Interest Rate Contract [Member] | Other Nonoperating Income (Expense) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments		0.0	0.0
Interest Rate Contract [Member] | Interest Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(4.2)	(9.0)	3.0
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Other Nonoperating Income (Expense) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		0.0	0.0
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Interest Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(2.1)	(2.5)	(4.2)
Operating Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Loss (Gain) Reclassified from Accumulated Other Comprehensive Income into Income	0.0	0.0	$ 0.1
Carrying Amount [Member]
Liabilities
Recourse fixed rate debt	5,056.3	4,389.3
Recourse floating rate debt	299.9	417.5
Estimate of Fair Value Measurement [Member]
Liabilities
Recourse fixed rate debt	5,696.9	4,644.6
Recourse floating rate debt	$ 300.4	$ 419.0