Troubled Debt Restructurings (Details) (Commercial Real Estate, USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Commercial Real Estate
Troubled Debt Restructurings
Recorded Investment in Troubled Debt Restructurings with Subsequent Default	$ 0	$ 4.3
Number of Troubled Debt Restructurings with Subsequent Default	0	1
Post-Modification Recorded Investment in Troubled Debt Restructurings on Loans Modified	18.1	0
Realized Loss on Troubled Debt Restructurings on Loans Modified	$ 3.0	$ 0
Number of Troubled Debt Restructurings due to Modified Terms	1	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

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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

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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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- Definition

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

+ References

+ Details

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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