Fair Value Of Financial Instruments (Schedule Of Comparison Of The Carrying Value And Estimated Fair Value Of These Financial Instruments) (Details) - USD ($) $ in Millions		Dec. 31, 2018		Dec. 31, 2017
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	[1]	$ 25.7		$ 8.2
Restricted cash and cash equivalents	[1]	303.6		255.6
Restricted securities available for sale	[2]	58.6		46.1
Net investment in Loans receivable	[1]	5,855.1		4,741.5
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit	[1]	171.9		13.9
Secured financing	[1]	3,100.9		2,527.6
Senior notes	[1]	556.3		569.4
Other Borrowings		11.9	[1]	0.0
Carrying Amount [Member]
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		25.7		8.2
Restricted cash and cash equivalents		303.6		255.6
Restricted securities available for sale		58.6		46.1
Net investment in Loans receivable		5,763.3		4,619.6
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit		171.9		13.9
Secured financing		3,092.7		2,514.1
Senior notes		544.4		542.8
Estimated Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		25.7		8.2
Restricted cash and cash equivalents		303.6		255.6
Restricted securities available for sale		58.6		46.1
Net investment in Loans receivable		5,855.1		4,741.5
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit		171.9		13.9
Secured financing		3,100.9		2,527.6
Senior notes		$ 556.3		$ 569.4

[1] Measured at amortized cost with fair value disclosed.

[2] Measured at fair value on a recurring basis.