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Investment Securities (Details 2) (USD $) In Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net realized investment gains (losses), pre-tax | $ 37.1 | $ 31.4 | $ 109.6 | $ 93.7
Net unrealized investment gains (losses), pre-tax | (35.4) | (19.8) | (31.3) | 11.0
Net realized and unrealized investment gains (losses), pre-tax | 1.7 | 11.6 | 78.3 | 104.7
Income taxes attributable to realized and unrealized investment gains (losses) | (1.1) | (22.7) | (23.7) | (24.5)
Net realized and unrealized investment gains (losses), after-tax | 0.6 | (11.1) | 54.6 | 80.2
Net realized investment gains (losses) |  |  |  |
Net realized investment gains (losses), pre-tax | 37.1 | 31.4 | 109.6 | 93.7
Income taxes attributable to realized investment gains (losses) | (8.0) | (4.9) | (31.7) | (20.5)
Net realized investment gains (losses), after-tax | 29.1 | 26.5 | 77.9 | 73.2
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | (110.0) | 79.4 | (110.3) | 80.4
Income taxes attributable to unrealized investment gains (losses) | 26.4 | (28.8) | 28.5 | (22.4)
Net unrealized investment gains (losses), after-tax | (83.6) | 50.6 | (81.8) | 58.0
Net unrealized investment gains (losses), net foreign exchange gains (losses), pre-tax | 74.6 | (99.2) | 79.0 | (69.4)
Income taxes attributable to unrealized investment gains, net foreign exchange gains (losses) | (19.5) | 11.0 | (20.5) | 18.4
Net unrealized investment gains (losses), net foreign exchange gains (losses), after tax | 55.1 | (88.2) | 58.5 | (51.0)
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | (35.4) | (19.8) | (31.3) | 11.0
Income taxes attributable to unrealized investment gains (losses), total changes in fair value reflected in earnings | 6.9 | (17.8) | 8.0 | (4.0)
Net unrealized investment gains (losses) after-tax, total changes in fair value reflected in earnings | (28.5) | (37.6) | (23.3) | 7.0
Fixed maturity investments |  |  |  |
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net realized investment gains (losses), pre-tax | 14.0 | 34.7 | 33.6 | 68.1
Net unrealized investment gains (losses), pre-tax | 71.0 | (77.9) | 90.3 | (17.2)
Net realized investment gains (losses) |  |  |  |
Net realized investment gains (losses), pre-tax | 14.0 | 34.7 | 33.6 | 68.1
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | 3.5 | 3.3 | 12.6 | 36.4
Net unrealized investment gains (losses), net foreign exchange gains (losses), pre-tax | 67.5 | (81.2) | 77.7 | (53.6)
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | 71.0 | (77.9) | 90.3 | (17.2)
Short-term investments |  |  |  |
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net unrealized investment gains (losses), pre-tax | (0.5) | 1.4 | (1.5) | 0.6
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | (0.1) |  | (0.1) |
Net unrealized investment gains (losses), net foreign exchange gains (losses), pre-tax | (0.4) | 1.4 | (1.4) | 0.6
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | (0.5) | 1.4 | (1.5) | 0.6
Common Equity Securities |  |  |  |
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net realized investment gains (losses), pre-tax | 23.1 | (13.7) | 41.0 | 6.7
Net unrealized investment gains (losses), pre-tax | (101.9) | 53.5 | (96.9) | 22.1
Net realized investment gains (losses) |  |  |  |
Net realized investment gains (losses), pre-tax | 23.1 | (13.7) | 41.0 | 6.7
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | (101.0) | 64.3 | (95.1) | 31.8
Net unrealized investment gains (losses), net foreign exchange gains (losses), pre-tax | (0.9) | (10.8) | (1.8) | (9.7)
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | (101.9) | 53.5 | (96.9) | 22.1
Convertible fixed maturity investments |  |  |  |
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net realized investment gains (losses), pre-tax | (0.7) | 6.2 | 6.3 | 19.9
Net unrealized investment gains (losses), pre-tax | (11.2) | 2.8 | (19.3) | (8.3)
Net realized investment gains (losses) |  |  |  |
Net realized investment gains (losses), pre-tax | (0.7) | 6.2 | 6.3 | 19.9
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | (11.2) | 2.8 | (19.3) | (8.3)
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | (11.2) | 2.8 | (19.3) | (8.3)
Other long-term investments. |  |  |  |
Net Realized and Unrealized Investment Gains and Losses |  |  |  |
Net realized investment gains (losses), pre-tax | 0.7 | 4.2 | 28.7 | (1.0)
Net unrealized investment gains (losses), pre-tax | 7.2 | 0.4 | (3.9) | 13.8
Net realized investment gains (losses) |  |  |  |
Net realized investment gains (losses), pre-tax | 0.7 | 4.2 | 28.7 | (1.0)
Net unrealized investment gains (losses) |  |  |  |
Net unrealized gains (losses), pre-tax | (1.2) | 9.0 | (8.4) | 20.5
Net unrealized investment gains (losses), net foreign exchange gains (losses), pre-tax | 8.4 | (8.6) | 4.5 | (6.7)
Net unrealized investment gains (losses) pre-tax, total changes in fair value reflected in earnings | $ 7.2 | $ 0.4 | $ (3.9) | $ 13.8

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- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -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 -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (c)-(e) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 22 -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 5 -Section 03 -Paragraph 7 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27405-111563 + Details
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- Definition This item represents the gain (loss) realized during the period from the sale of trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 5 -Section 03 -Paragraph 7 -Subparagraph c Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c)) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 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 + Details
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- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of trading securities held at each balance sheet date, that was included in earnings for the period. Trading securities are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) and the change in net unrealized holding gain (loss) is included in earnings for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c)) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 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 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 -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 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 FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph e -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 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6956420&loc=d3e24584-111560 + Details
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- Definition The after-tax aggregate of the change in unrealized holding gain (loss) and foreign currency gain (loss) included in earnings during the reporting period. + Details
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- Definition The tax expense (benefit) attributable to the aggregate of the change in unrealized holding gain (loss) and foreign currency gain (loss) included in earnings during the reporting period. + Details
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