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Non-controlling Interests (Tables) | 3 Months Ended
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Mar. 31, 2021
Noncontrolling Interest [Abstract] |
Non-controlling Interests | The following table presents 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 March 31, 2021 and December 31, 2020:
|  | March 31, 2021 |  | December 31, 2020
$ in Millions |  | Non-controlling Percentage |  | Non-controlling Equity |  | Non-controlling Percentage |  | Non-controlling Equity
Non-controlling interests, excluding BAM |  |  |  |  |  |  |  |
HG Global |  | 3.1 | % |  | $ | 11.6 |  |  | 3.1 | % |  | $ | 13.5 |
Ark |  | 28.0 | % |  | 211.0 |  |  | — | % |  | — |
NSM |  | 3.4 | % |  | 16.0 |  |  | 3.4 | % |  | 17.0 |
Kudu |  | .7 | % |  | 2.3 |  |  | .7 | % |  | 2.3 |
Other |  | various |  | 2.0 |  |  | various |  | 2.4 |
Total, excluding BAM |  |  |  | 242.9 |  |  |  |  | 35.2 |
BAM |  | 100.0 | % |  | (132.9) |  |  | 100.0 | % |  | (123.3) |
Total non-controlling interests |  |  |  | $ | 110.0 |  |  |  |  | $ | (88.1) |

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