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Investments in Unconsolidated Affiliates (Details 3) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2010 | Sep. 30, 2010 | Jun. 30, 2010 | Mar. 31, 2010 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Changes in carrying value of investment in Symetra |  |  |  |  |  |  |  |  |  |  |
Carrying value at the beginning of the period |  |  |  | $ 389.7 |  |  |  |  | $ 389.7 |  |
Equity in earnings of Symetra | (36.3) | 1.5 | 7.9 | 6.7 | 8.3 | 7.9 | 5.3 | (11.6) | (20.2) | 9.9 | 24.3
Carrying value at the end of the period | 275.3 |  |  |  | 389.7 |  |  |  | 275.3 | 389.7 |
Symetra |  |  |  |  |  |  |  |  |  |  |
Changes in carrying value of investment in Symetra |  |  |  |  |  |  |  |  |  |  |
Carrying value at the beginning of the period |  |  |  | 387.5 |  |  |  | 307.7 | 387.5 | 307.7 | 81.3
Equity in earnings of Symetra |  |  |  |  |  |  |  |  | 28.2 | 11.1 | 23.9
Impairment of equity in earnings of investee |  |  |  |  |  |  |  |  | (50.0) |  |
Net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | 85.0 | 72.7 | 191.3
Impairment of net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | (148.6) |  |
Dividends received |  |  |  |  |  |  |  |  | (4.0) | (2.6) |
Decrease (increase) in value of warrants |  |  |  |  |  |  |  |  | (24.5) | (1.4) | 11.2
Carrying value at the end of the period | 273.6 |  |  |  | 387.5 |  |  |  | 273.6 | 387.5 | 307.7
Tax on equity in earnings |  |  |  |  |  |  |  |  | 2.3 | 1.4 | 0
Equity in net unrealized gains (losses) |  |  |  |  |  |  |  |  |  | 63.7 | (9.0)
Tax on equity in net unrealized gains (losses) |  |  |  |  |  |  |  |  | 0 | 5.2 | 0
Loss from dilutive effect resulting from public offering |  |  |  |  |  |  |  |  |  | 17.9 |
Gain from dilutive effect resulting from public offering |  |  |  |  |  |  |  |  |  | 1.9 |
Tax on net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | (6.9) | 0.8 | 0
Loss from dilutive effect resulting from dividend and issuance of restricted shares |  |  |  |  |  |  |  |  | 1.0 | 0.8 | 0
Cash dividends received on warrants |  |  |  |  |  |  |  |  | 2.2 |  |
Symetra | Common shareholders' equity. |  |  |  |  |  |  |  |  |  |  |
Changes in carrying value of investment in Symetra |  |  |  |  |  |  |  |  |  |  |
Carrying value at the beginning of the period |  |  |  | 350.4 |  |  |  | 269.2 | 350.4 | 269.2 | 54.0
Equity in earnings of Symetra |  |  |  |  |  |  |  |  | 28.2 | 11.1 | 23.9
Impairment of equity in earnings of investee |  |  |  |  |  |  |  |  | (50.0) |  |
Net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | 85.0 | 72.7 | 191.3
Impairment of net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | (148.6) |  |
Dividends received |  |  |  |  |  |  |  |  | (4.0) | (2.6) |
Carrying value at the end of the period | 261.0 |  |  |  | 350.4 |  |  |  | 261.0 | 350.4 | 269.2
Tax benefit on impairment of equity in earnings |  |  |  |  |  |  |  |  | 4.1 |  |
Impairment of net unrealized gains from investee's fixed maturity portfolio |  |  |  |  |  |  |  |  | 12.0 |  |
Symetra | Warrants |  |  |  |  |  |  |  |  |  |  |
Changes in carrying value of investment in Symetra |  |  |  |  |  |  |  |  |  |  |
Carrying value at the beginning of the period |  |  |  | 37.1 |  |  |  | 38.5 | 37.1 | 38.5 | 27.3
Decrease (increase) in value of warrants |  |  |  |  |  |  |  |  | (24.5) | (1.4) | 11.2
Carrying value at the end of the period | $ 12.6 |  |  |  | $ 37.1 |  |  |  | $ 12.6 | $ 37.1 | $ 38.5

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