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Investment Securities (Mortgage-backed, Asset-backed Securities) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2014 Fixed rate CMBS | Mar. 31, 2014 Maximum Commercial Mortgage Backed Securities | Mar. 31, 2014 Fair Value | Dec. 31, 2013 Fair Value | Mar. 31, 2013 Fair Value | Dec. 31, 2012 Fair Value | Mar. 31, 2014 Fair Value Fixed rate CMBS | Mar. 31, 2014 Fair Value Floating rate CMBS | Mar. 31, 2014 Fair Value Commercial Mortgage Backed Securities | Dec. 31, 2013 Fair Value Commercial Mortgage Backed Securities | Mar. 31, 2014 Fair Value Non-Agency Residential Mortgage Resecuritization
Investment securities |  |  |  |  |  |  |  |  |  |  |
Average basis points of subordination | 0.25 |  |  |  |  |  |  |  |  |  |
Percentage of underlying loans reported as non-performing |  | 1.00% |  |  |  |  |  |  |  |  |
Fair value investments |  |  | $ 6,736.7 | $ 6,766.5 | $ 6,580.6 | $ 6,950.7 | $ 225.1 | $ 104.6 | $ 329.7 | $ 282.3 | $ 37.8

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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 + Details
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- Definition Reflects the percentage derived from dividing impaired loans on which interest has ceased to be accrued by total loans. + References No definition available. + Details
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- Definition Basis points of subordination on average. + References No definition available. + Details
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