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Non-controlling Interest (Tables) | 9 Months Ended
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Sep. 30, 2017
Noncontrolling Interest [Abstract] |
Non-controlling Interests | The following table details the balance of non-controlling interests included in White Mountains’s total equity and the related percentage of each consolidated entity’s total equity owned by non-controlling shareholders as of September 30, 2017 and December 31, 2016:
|  | September 30, 2017 |  | December 31, 2016
$ in millions |  | Non-controlling Percentage |  | Non-controlling Equity |  | Non-controlling Percentage |  | Non-controlling Equity
OneBeacon Ltd. |  | — | % |  | $ | — |  |  | 23.9 | % |  | $ | 244.6 |
Other, excluding mutuals and reciprocals |  |  |  |  |  |  |  |
HG Global |  | 3.1 |  |  | 16.1 |  |  | 3.1 |  |  | 16.6 |
MediaAlpha |  | 40.0 |  |  | 9.5 |  |  | 40.0 |  |  | 11.7 |
Buzzmove |  | 22.9 |  |  | 3.0 |  |  | 29.1 |  |  | 2.9 |
Wobi |  | 5.0 |  |  | — |  |  | 5.0 |  |  | .1 |
Dewar (1) |  | — |  |  | — |  |  | 18.8 |  |  | 3.9 |
Total other, excluding mutuals and reciprocals |  |  |  | 28.6 |  |  |  |  | 35.2 |
Mutuals and reciprocals |  |  |  |  |  |  |  |
BAM |  | 100.0 |  |  | (160.2 | ) |  | 100.0 |  |  | (150.9 | )
SSIE |  | — |  |  | — |  |  | 100.0 |  |  | 4.4 |
Total mutuals and reciprocals |  |  |  | (160.2 | ) |  |  |  | (146.5 | )
Total non-controlling interests |  |  |  |  | $ | (131.6 | ) |  |  |  | $ | 133.3 |
(1) Dewar is a subsidiary of OneBeacon.

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