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Investment Securities (Details 8) (USD $) In Millions, unless otherwise specified |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 Months Ended |  | 3 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Mar. 31, 2012 Fair Value | Dec. 31, 2011 Fair Value | Mar. 31, 2011 Fair Value | Dec. 31, 2010 Fair Value | Mar. 31, 2012 Level 2 Inputs | Dec. 31, 2011 Level 2 Inputs | Mar. 31, 2011 Level 2 Inputs | Dec. 31, 2010 Level 2 Inputs | Mar. 31, 2012 Mortgage-backed and asset-backed securities Fair Value | Dec. 31, 2011 Mortgage-backed and asset-backed securities Fair Value | Mar. 31, 2012 Mortgage-backed and asset-backed securities Level 2 Inputs | Dec. 31, 2011 Mortgage-backed and asset-backed securities Level 2 Inputs | Mar. 31, 2012 Mortgage-backed and asset-backed securities Level 3 Inputs | Dec. 31, 2011 Mortgage-backed and asset-backed securities Level 3 Inputs | Mar. 31, 2012 Mortgage-backed securities Fair Value | Dec. 31, 2011 Mortgage-backed securities Fair Value | Mar. 31, 2012 Mortgage-backed securities Level 2 Inputs | Dec. 31, 2011 Mortgage-backed securities Level 2 Inputs | Mar. 31, 2012 Mortgage-backed securities Level 3 Inputs | Dec. 31, 2011 Mortgage-backed securities Level 3 Inputs | Mar. 31, 2012 Agency mortgage-backed securities Fair Value | Dec. 31, 2011 Agency mortgage-backed securities Fair Value | Mar. 31, 2012 Agency mortgage-backed securities Level 2 Inputs | Dec. 31, 2011 Agency mortgage-backed securities Level 2 Inputs | Mar. 31, 2012 Agency mortgage-backed securities Level 3 Inputs | Mar. 31, 2012 GNMA Fair Value | Dec. 31, 2011 GNMA Fair Value | Mar. 31, 2012 GNMA Level 2 Inputs | Dec. 31, 2011 GNMA Level 2 Inputs | Mar. 31, 2012 FNMA Fair Value | Dec. 31, 2011 FNMA Fair Value | Mar. 31, 2012 FNMA Level 2 Inputs | Dec. 31, 2011 FNMA Level 2 Inputs | Mar. 31, 2012 FHLMC Fair Value | Dec. 31, 2011 FHLMC Fair Value | Mar. 31, 2012 FHLMC Level 2 Inputs | Dec. 31, 2011 FHLMC Level 2 Inputs | Mar. 31, 2012 FHLMC Level 3 Inputs | Mar. 31, 2012 Non-agency mortgage-backed securities 2003 | Mar. 31, 2012 Non-agency mortgage-backed securities 2006 | Mar. 31, 2012 Non-agency mortgage-backed securities 2007 | Mar. 31, 2012 Non-agency mortgage-backed securities 2009 | Mar. 31, 2012 Non-agency mortgage-backed securities 2010 | Mar. 31, 2012 Non-agency mortgage-backed securities 2011 | Mar. 31, 2012 Non-agency mortgage-backed securities 2012 | Mar. 31, 2012 Non-agency mortgage-backed securities Fair Value | Dec. 31, 2011 Non-agency mortgage-backed securities Fair Value | Mar. 31, 2012 Non-agency mortgage-backed securities Level 2 Inputs | Dec. 31, 2011 Non-agency mortgage-backed securities Level 2 Inputs | Mar. 31, 2012 Non-agency mortgage-backed securities Level 3 Inputs | Dec. 31, 2011 Non-agency mortgage-backed securities Level 3 Inputs | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Super Senior | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Super Senior Prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Super Senior Non-prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Senior | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Senior Prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Senior Non-prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) 2003 | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) 2006 | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) 2007 | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) 2010 | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) 2011 | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Fair Value | Dec. 31, 2011 Non-agency residential mortgage-backed securities (RMBS) Fair Value | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Fair Value Prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Fair Value Non-prime | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Level 2 Inputs | Dec. 31, 2011 Non-agency residential mortgage-backed securities (RMBS) Level 2 Inputs | Mar. 31, 2012 Non-agency residential mortgage-backed securities (RMBS) Level 3 Inputs | Dec. 31, 2011 Non-agency residential mortgage-backed securities (RMBS) Level 3 Inputs | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) Super Senior | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) Senior | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) 2007 | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) 2009 | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) 2010 | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) 2011 | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) 2012 | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) Fair Value | Dec. 31, 2011 Non-agency commercial mortgage-backed securities (CMBS) Fair Value | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) Level 2 Inputs | Dec. 31, 2011 Non-agency commercial mortgage-backed securities (CMBS) Level 2 Inputs | Mar. 31, 2012 Non-agency commercial mortgage-backed securities (CMBS) Maximum | Mar. 31, 2012 Fixed Rate CMBS | Mar. 31, 2012 Fixed Rate CMBS Super Senior | Mar. 31, 2012 Fixed Rate CMBS Senior | Mar. 31, 2012 Fixed Rate CMBS Fair Value | Mar. 31, 2012 Floating Rate CMBS | Mar. 31, 2012 Floating Rate CMBS Super Senior | Mar. 31, 2012 Floating Rate CMBS Senior | Mar. 31, 2012 Floating Rate CMBS Fair Value | Mar. 31, 2012 Other asset-backed securities Fair Value | Dec. 31, 2011 Other asset-backed securities Fair Value | Mar. 31, 2012 Other asset-backed securities Level 2 Inputs | Dec. 31, 2011 Other asset-backed securities Level 2 Inputs | Mar. 31, 2012 Credit card receivables Fair Value | Dec. 31, 2011 Credit card receivables Fair Value | Mar. 31, 2012 Credit card receivables Level 2 Inputs | Dec. 31, 2011 Credit card receivables Level 2 Inputs | Mar. 31, 2012 Vehicle receivables Fair Value | Dec. 31, 2011 Vehicle receivables Fair Value | Mar. 31, 2012 Vehicle receivables Level 2 Inputs | Dec. 31, 2011 Vehicle receivables Level 2 Inputs | Mar. 31, 2012 Other Fair Value | Dec. 31, 2011 Other Fair Value | Mar. 31, 2012 Other Level 2 Inputs | Dec. 31, 2011 Other Level 2 Inputs
Mortgage-backed, Asset-backed Securities Abstract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Average basis points of subordination (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.002 |  |  |  | 0.0045 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of underlying loans reported as non-performing |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value investments | $ 7,583.8 | $ 8,346.8 | $ 7,784.8 | $ 7,901.6 | $ 5,115.0 | $ 6,088.2 | $ 5,498.5 | $ 5,477.4 | $ 2,151.2 | $ 3,222.9 | $ 2,062.9 | $ 3,207.8 | $ 88.3 | $ 15.1 | $ 1,995.5 | $ 2,474.1 | $ 1,907.2 | $ 2,459.0 | $ 88.3 | $ 15.1 | $ 1,614.9 | $ 2,114.3 | $ 1,541.7 | $ 2,114.3 | $ 73.2 | $ 1,200.3 | $ 1,365.8 | $ 1,200.3 | $ 1,365.8 | $ 308.2 | $ 712.6 | $ 308.2 | $ 712.6 | $ 106.4 | $ 35.9 | $ 33.2 | $ 35.9 | $ 73.2 | $ 2.9 | $ 22.7 | $ 43.1 | $ 11.3 | $ 16.8 | $ 266.6 | $ 17.2 | $ 380.6 | $ 359.8 | $ 365.5 | $ 344.7 | $ 15.1 | $ 15.1 | $ 33.4 | $ 18.3 | $ 15.1 | $ 48.1 | $ 47.4 | $ 0.7 | $ 2.9 | $ 22.7 | $ 25.4 | $ 10.5 | $ 20.0 | $ 81.5 | $ 83.1 | $ 65.7 | $ 15.8 | $ 66.4 | $ 68.0 | $ 15.1 | $ 15.1 | $ 80.5 | $ 218.6 | $ 17.7 | $ 11.3 | $ 6.3 | $ 246.6 | $ 17.2 | $ 299.1 | $ 276.7 | $ 299.1 | $ 276.7 |  |  | $ 62.8 | $ 208.7 | $ 271.5 |  | $ 17.7 | $ 9.9 | $ 27.6 | $ 155.7 | $ 748.8 | $ 155.7 | $ 748.8 | $ 81.5 | $ 380.6 | $ 81.5 | $ 380.6 | $ 43.0 | $ 345.6 | $ 43.0 | $ 345.6 | $ 31.2 | $ 22.6 | $ 31.2 | $ 22.6

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include 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 -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: 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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 7 -Section 03 -Paragraph 1 -Subparagraph a, f, g Reference 7: 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=6956420&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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- Details
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