Investments Troubled Debt Restructurings on Financing Receivables (Details) (Commercial Real Estate Portfolio Segment, USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commercial Real Estate Portfolio Segment
Financing Receivable Modifications
Recorded Investment in Mortgage Loan Modifications Due to Foreclosure	$ 18.1	$ 4.3	$ 17.3
Number of Modifications Due to Loan Foreclosure	1	1	3

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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