Investments (Troubled Debt Restructurings on Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015 NumberOfLoans	Mar. 31, 2014 NumberOfLoans
Financing Receivable, Modifications [Line Items]
Number of Loans	5
Pre-Restructuring Recorded Investment	$ 2.6
Post-Restructuring Recorded Investment	2.7
Retail [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	3
Pre-Restructuring Recorded Investment	1.5
Post-Restructuring Recorded Investment	1.5
Office [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	2
Pre-Restructuring Recorded Investment	1.1
Post-Restructuring Recorded Investment	1.2
Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	2
Pre-Restructuring Recorded Investment	0	1.7
Post-Restructuring Recorded Investment	0	1.9
Hotels and Motels [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0
Pre-Restructuring Recorded Investment	0
Post-Restructuring Recorded Investment	0
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0
Pre-Restructuring Recorded Investment	0
Post-Restructuring Recorded Investment	0
Apartment and Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0
Pre-Restructuring Recorded Investment	0
Post-Restructuring Recorded Investment	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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