Debt (Scheduled Principal Maturities Of Debt) (Details) $ in Millions	Dec. 31, 2018 USD ($)
2019	$ 1,048.6
2020	1,339.2
2021	1,194.6
2022	0.7
2023	259.4
After 2023	0.0
Total	3,842.5
Revolving Secured Line Of Credit [Member]
2019	0.0
2020	0.0
2021	171.9
2022	0.0
2023	0.0
After 2023	0.0
Total	171.9
Secured Debt [Member]
2019	0.0
2020	0.0
2021	0.0
2022	0.0
2023	0.0
After 2023	0.0
Total	0.0
Term ABS Financing [Member]
2019	1,048.0	[1]
2020	1,338.6	[1]
2021	722.1	[1]
2022	0.0	[1]
2023	0.0	[1]
After 2023	0.0	[1]
Total	3,108.7	[1]
Senior Notes [Member]
2019	0.0
2020	0.0
2021	300.0
2022	0.0
2023	250.0
After 2023	0.0
Total	550.0
Mortgage [Member]
2019	0.6
2020	0.6
2021	0.6
2022	0.7
2023	9.4
After 2023	0.0
Total	$ 11.9

[1] The principal maturities of the Term ABS transactions are estimated based on forecasted collections.