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	Sep. 30, 2014	Dec. 31, 2013
Assets
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
Liabilities
Revolving secured line of credit	8.8	102.8
Secured financing	1,356.9	938.9
Mortgages [Member]
Liabilities
Notes		3.8
Senior Notes [Member]
Liabilities
Notes	307.9	367.1
Carrying Amount [Member]
Assets
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	2,407.4	2,212.8
Liabilities
Revolving secured line of credit	8.8	102.8
Secured financing	1,351.3	935.6
Carrying Amount [Member] \| Mortgages [Member]
Liabilities
Notes	0	3.8
Carrying Amount [Member] \| Senior Notes [Member]
Liabilities
Notes	300.0	350.2
Estimated Fair Value [Member]
Assets
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
Liabilities
Revolving secured line of credit	8.8	102.8
Secured financing	1,356.9	938.9
Estimated Fair Value [Member] \| Mortgages [Member]
Liabilities
Notes	0	3.8
Estimated Fair Value [Member] \| Senior Notes [Member]
Liabilities
Notes	$ 307.9	$ 367.1

Restricted Cash And Cash Equivalents, Fair Value Disclosure

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- Definition

Secured Financing Fair Value Disclosure

+ References

No definition available.

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- Definition

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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph b

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Line-of-Credit Arrangement

-URI http://asc.fasb.org/extlink&oid=6517033

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- Definition

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

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

Fair value portion of notes payable.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-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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