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Investment Securities (Investment Holdings) (Details) (USD $) In Millions, unless otherwise specified |  |  | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2012 Including Short Term Fixed | Dec. 31, 2012 US Government and agency obligations | Dec. 31, 2011 US Government and agency obligations | Dec. 31, 2012 Debt securities issued by industrial corporations | Dec. 31, 2011 Debt securities issued by industrial corporations | Dec. 31, 2012 Municipal obligations | Dec. 31, 2011 Municipal obligations | Dec. 31, 2012 Mortgage-backed and asset-backed securities | Dec. 31, 2011 Mortgage-backed and asset-backed securities | Dec. 31, 2012 Foreign government, agency and provincial obligations | Dec. 31, 2011 Foreign government, agency and provincial obligations | Dec. 31, 2012 Preferred stocks | Dec. 31, 2011 Preferred stocks | Dec. 31, 2012 Fixed Income Investments [Member] | Dec. 31, 2011 Fixed Income Investments [Member] | Dec. 31, 2012 Excluding Short Term Investments
Investment securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Duration of Fixed Maturities including short-term investments in years |  |  |  |  | 2 years 4 months 24 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years 8 months 12 days
Cost or amortized cost | $ 5,576.3 |  |  |  |  | $ 440.4 | $ 299.4 | $ 2,321.4 | $ 2,072.1 | $ 5.3 | $ 2.7 | $ 2,081.0 | $ 3,190.5 | $ 526.6 | $ 581.2 | $ 79.9 | $ 82.3 | $ 5,454.6 | $ 6,228.2 |
Gross unrealized gains |  |  |  |  |  | 1.0 | 5.3 | 88.3 | 73.7 | 0 | 0 | 25.1 | 25.9 | 6.9 | 11.0 | 6.7 | 3.2 | 128.0 | 119.1 |
Gross unrealized losses |  |  |  |  |  | (0.1) | (0.1) | (1.6) | (7.8) | (0.1) | 0 | (1.1) | (3.9) | (3.0) | (0.1) | 0 | (6.7) | (5.9) | (18.6) |
Net foreign currency losses |  |  |  |  |  | (1.2) | 0.4 | (23.0) | (2.9) | 0 | 0 | (9.4) | 10.4 | (8.6) | (2.9) | (0.2) | 0 | (42.4) | 5.0 |
Total fixed maturity investments including assets held for sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,534.3 | 6,333.7 |
Fixed maturity investments reclassified to assets held for sale (1) | (338.1) | [1] | (111.8) | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity investments, at fair value | $ 5,196.2 |  | $ 6,221.9 |  |  | $ 440.1 | $ 305.0 | $ 2,385.1 | $ 2,135.1 | $ 5.2 | $ 2.7 | $ 2,095.6 | $ 3,222.9 | $ 521.9 | $ 589.2 | $ 86.4 | $ 78.8 |  |  |
[1] | Assets held for sale related to discontinued operations. See Note 20.

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- Definition Debt securities that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: 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 6: 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 7: 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 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 29 -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 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Implementation Guide (Q and A) -Number FAS115 -Paragraph 35 -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. + Details
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