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Investments in Unconsolidated Affiliates (Details 3) (USD $) In Millions, except Per Share data, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2012 | Mar. 31, 2011
Changes in carrying value of investment in Symetra |  |
Carrying value at the beginning of the period | $ 275.3 |
Equity in earnings | 10.2 | 6.7
Carrying value at the end of the period | 294.9 |
Symetra |  |
Changes in carrying value of investment in Symetra |  |
Carrying value at the beginning of the period | 273.6 | 387.5
Equity in earnings | 10.9 | 7.3
Equity in net unrealized losses from Symetra's fixed maturity portfolio | (1.2) |
Dividends received | (1.2) | (0.8)
Increase (decrease) in value of warrants | 11.1 | (1.2)
Carrying value at the end of the period | 293.2 | 392.8
Tax on equity in earnings | 0.7 | 0.6
Tax on equity in net unrealized gains (losses) | 0 | 5.2
Aggregate value of White Mountains common shares of Symetra at quoted market price | 200.6 |
Quoted market price (in dollars per share) | $ 11.53 |
Cash dividends received on warrants | 1.2 |
Symetra | Common shareholders' equity. |  |
Changes in carrying value of investment in Symetra |  |
Carrying value at the beginning of the period | 261.0 | 350.4
Equity in earnings | 10.9 | 7.3
Equity in net unrealized losses from Symetra's fixed maturity portfolio | (1.2) |
Dividends received | (1.2) | (0.8)
Carrying value at the end of the period | 269.5 | 356.9
Equity in earnings increase relating to amortization of common share impairment | 1.1 |
Equity in net unrealized losses increase relating to amortization of common share impairment | 3.2 |
Symetra | Warrants |  |
Changes in carrying value of investment in Symetra |  |
Carrying value at the beginning of the period | 12.6 | 37.1
Increase (decrease) in value of warrants | 11.1 | (1.2)
Carrying value at the end of the period | 23.7 | 35.9
Cash dividends received on warrants | $ 0.7 |

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- Definition The net unrealized gains (losses) from Symetra's fixed maturity portfolio. + References No definition available. + Details
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