Fair Value of Financial Instruments (Schedule of Comparison of the Carrying Value and Estimated Fair Value of Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 86.7	$ 6.4
Restricted cash and cash equivalents	198.9	157.6
Restricted securities available for sale	53.0	53.2
Net investment in Loans receivable	2,739.4	2,517.3
Liabilities
Revolving secured line of credit		119.5
Secured financing	1,438.1	1,334.7
Senior Notes [Member]
Liabilities
Notes	535.8	299.3
Carrying Amount [Member]
Assets
Cash and cash equivalents	86.7	6.4
Restricted cash and cash equivalents	198.9	157.6
Restricted securities available for sale	53.0	53.2
Net investment in Loans receivable	2,733.2	2,512.9
Liabilities
Revolving secured line of credit	0	119.5
Secured financing	1,435.3	1,333.0
Carrying Amount [Member] \| Senior Notes [Member]
Liabilities
Notes	548.2	300.0
Estimated Fair Value [Member]
Assets
Cash and cash equivalents	86.7	6.4
Restricted cash and cash equivalents	198.9	157.6
Restricted securities available for sale	53.0	53.2
Net investment in Loans receivable	2,739.4	2,517.3
Liabilities
Revolving secured line of credit	0	119.5
Secured financing	1,438.1	1,334.7
Estimated Fair Value [Member] \| Senior Notes [Member]
Liabilities
Notes	$ 535.8	$ 299.3

Restricted Cash And Cash Equivalents, Fair Value Disclosure

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Secured Financing Fair Value Disclosure

+ References

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The carrying amount of securities categorized neither as held-to-maturity nor trading which serve as security for borrowings or other arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX210.4-08(b))

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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-Name Accounting Standards Codification

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

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Fair value portion of notes payable.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20,22)

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