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Investments in Unconsolidated Affiliates (Tables) | 6 Months Ended
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Jun. 30, 2016
Equity Method Investments and Joint Ventures [Abstract] |
Schedule of Changes in Investments in Unconsolidated Affiliates | The following table summarizes amounts recorded by White Mountains under the equity method relating to its investment in Symetra for the three and six months ended June 30, 2015:
|  | Three Months Ended |  | Six Months Ended
Millions |  | June 30, 2015 |  | June 30, 2015
Equity method carrying value of investment in Symetra at the beginning of the period |  | $ | 447.3 |  |  | $ | 411.4 |
Equity in earnings (1)(2) |  | 6.1 |  |  | 13.3 |
Equity in net unrealized losses from Symetra’s fixed maturity portfolio (3) |  | (66.4 | ) |  | (35.5 | )
Dividends received |  | (2.2 | ) |  | (4.4 | )
Distribution from Prospector Offshore Fund |  | 12.4 |  |  | 12.4 |
Equity method carrying value of investment in Symetra at the end of the period(4) |  | $ | 397.2 |  |  | $ | 397.2 |
(1) For the three and six months ended June 30, 2015, equity in earnings excludes tax expense of $0.4 and $0.8. (2) For the three and six months ended June 30, 2015, equity in earnings includes $0.7 and $1.4 increase relating to the pre-tax amortization of the Symetra common share basis difference. (3) For the three and six months ended June 30, 2015, net unrealized gains includes $2.8 and $5.7 increase relating to the pre-tax amortization of the Symetra common share basis difference. (4) Includes White Mountains’s equity in net unrealized gains from Symetra’s fixed maturity portfolio of $2.0 as of June 30, 2015, which excludes tax expense of $0.0.

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