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, 2016	Dec. 31, 2015
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	$ 14.6	$ 6.3
Restricted cash and cash equivalents	224.7	167.4
Restricted securities available for sale	45.3	48.3
Net investment in Loans receivable	3,955.9	3,126.3
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit	0.0	57.7
Secured financing	2,072.0	1,471.9
Senior notes	560.5	549.6
Carrying Amount [Member]
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	14.6	6.3
Restricted cash and cash equivalents	224.7	167.4
Restricted securities available for sale	45.3	48.3
Net investment in Loans receivable	3,886.6	3,101.5
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit	0.0	57.7
Secured financing	2,062.4	1,470.1
Senior notes	541.3	540.0
Estimated Fair Value [Member]
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	14.6	6.3
Restricted cash and cash equivalents	224.7	167.4
Restricted securities available for sale	45.3	48.3
Net investment in Loans receivable	3,955.9	3,126.3
Liabilities, Fair Value Disclosure [Abstract]
Revolving secured line of credit	0.0	57.7
Secured financing	2,072.0	1,471.9
Senior notes	$ 560.5	$ 549.6