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Investments in Unconsolidated Affiliates (Tables) | 3 Months Ended
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Mar. 31, 2015
Equity Method Investments and Joint Ventures [Abstract] |
Investments in and Advances to Affiliates | White Mountains’s investments in unconsolidated affiliates represent investments in other companies in which White Mountains has a significant voting and economic interest but does not control the entity.
Millions |  | March 31, 2015 |  | December 31, 2014
Symetra common shares |  | $ | 378.9 |  |  | $ | 373.8 |
Unrealized gains from Symetra’s fixed maturity portfolio |  | 68.4 |  |  | 37.6 |
Carrying value of Symetra common shares |  | 447.3 |  |  | 411.4 |
Hamer |  | 3.5 |  |  | 3.0 |
Total investments in unconsolidated affiliates |  | $ | 450.8 |  |  | $ | 414.4 |
Schedule of Changes in Investments in Unconsolidated Affiliates | The following table summarizes amounts recorded by White Mountains relating to its investment in Symetra for the three months ended March 31, 2015 and 2014:
|  | Three Months Ended
|  | March 31,
Millions |  | 2015 |  | 2014
Carrying value of investment in Symetra at beginning of period |  | $ | 411.4 |  |  | $ | 317.3 |
Equity in earnings (1)(2) |  | 7.2 |  |  | 14.4 |
Equity in net unrealized gains (losses) from Symetra’s fixed maturity portfolio(3) |  | 30.9 |  |  | 39.3 |
Dividends received |  | (2.2 | ) |  | (2.0 | )
Carrying value of investment in Symetra at end of period(4)(5) |  | $ | 447.3 |  |  | $ | 369.0 |
(1) Equity in earnings excludes tax expense of $0.4 and $1.0. (2) Equity in earnings includes $0.7 and $0.7 increase relating to the pre-tax amortization of the Symetra common share basis difference. (3) Net unrealized gains includes $2.9 and $3.1 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 $68.4 and $39.3 as of March 31, 2015 and 2014, which excludes tax expense of $4.6 and $2.8. (5) The aggregate value of White Mountains’s investment in common shares of Symetra was $470.3 based upon the quoted market price of $23.46 per share at March 31, 2015.

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- Definition Tabular disclosure of investments in and advances to affiliates. Does not include the tabular disclosure of the disaggregation of investments in and advances to affiliates across legal entities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14) -URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611322-123010 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 14 -Article 12 + Details
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