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Investments in Unconsolidated Affiliates (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | --- | --- | ---
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Investments in unconsolidated affiliates | $ 321.4 |  | $ 387.9 |  |  |  |
Symetra |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Unrealized (losses) gains from Symetra’s fixed maturity portfolio | (43.6) |  | 62.8 |  |  |  |
Investments in unconsolidated affiliates | 317.3 | [1],[2] | 381.5 | [3] | 273.6 | [3] | 387.5
Symetra | Common Stock |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Symetra common shares | 360.9 |  | 288.4 |  |  |  |
Investments in unconsolidated affiliates | 317.3 | [1],[2] | 351.2 | [3] | 261.0 | [3] | 350.4
Symetra | Warrants |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Investments in unconsolidated affiliates | 0 | [1],[2] | 30.3 | [3] | 12.6 | [3] | 37.1
Hamer, LLC |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Investments in unconsolidated affiliates | 4.1 | [4] | 4.0 | [4] |  |  |
Bri-Mar Manufacturing, LLC |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Investments in unconsolidated affiliates | 0 | [4] | 1.9 | [4] |  |  |
Pentelia Capital Management |  |  |  |  |  |  |
Investments in unconsolidated affiliates |  |  |  |  |  |  |
Investments in unconsolidated affiliates | $ 0 |  | $ 0.5 |  |  |  |
[1] | Equity in earnings for the years end December 31, 2013, 2012 and 2011 excludes tax expense of $2.8, $2.6, and $2.3
[2] | The aggregate value of White Mountains’ investment in common shares of Symetra was $380.1 based upon the quoted market price of $18.96 per share at December 31, 2013.
[3] | Includes White Mountains’ equity in net unrealized (losses) gains from Symetra’s fixed maturity portfolio of $(43.6), $62.8, and $0 as of December 31, 2013, 2012 and 2011, which excludes tax benefit (expense) of $3.2, $(5.1) and $0
[4] | As of October 1, 2012, Hamer and Bri-Mar are no longer consolidated and are accounted for as investments in unconsolidated affiliates.

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- Definition Total investments in (A) companies that are accounted for using the equity method and (B) warrants to acquire additional shares of an unconsolidated affiliate that are carried at fair value. + References No definition available. + Details
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