Fair Value of Financial Instruments (Schedule of Assets and Liabilities, Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 4.3	$ 4.2
Restricted cash and cash equivalents	205.4	111.3
Restricted securities available for sale	51.4	53.6
Net investment in Loans receivable	2,417.2	2,226.7
Revolving secured line of credit	8.8	102.8
Secured financing	1,356.9	938.9
Mortgages [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes		3.8
Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes	307.9	367.1
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4.3	4.2
Restricted cash and cash equivalents	205.4	111.3
Restricted securities available for sale	47.9	25.1
Net investment in Loans receivable
Revolving secured line of credit
Secured financing
Level 1 [Member] | Mortgages [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes
Level 1 [Member] | Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes	307.9	367.1
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents
Restricted cash and cash equivalents
Restricted securities available for sale	3.5	28.5
Net investment in Loans receivable
Revolving secured line of credit	8.8	102.8
Secured financing	1,356.9	938.9
Level 2 [Member] | Mortgages [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes		3.8
Level 2 [Member] | Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents
Restricted cash and cash equivalents
Restricted securities available for sale
Net investment in Loans receivable	2,417.2	2,226.7
Revolving secured line of credit
Secured financing
Level 3 [Member] | Mortgages [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes
Level 3 [Member] | Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes