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Noncontrolling Interests (Tables) | 9 Months Ended
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Sep. 30, 2024
Noncontrolling Interest [Abstract] |
Non-controlling interests | The following table presents the balance of noncontrolling interests included in White Mountains’s total equity and the related percentage of each consolidated entity’s total equity owned by noncontrolling shareholders as of September 30, 2024 and December 31, 2023:
|  | September 30, 2024 |  | December 31, 2023 |
$ in Millions |  | Noncontrolling Percentage (1) |  | Noncontrolling Equity |  | Noncontrolling Percentage (1) |  | Noncontrolling Equity |
Noncontrolling interests, excluding BAM |  |  |  |  |  |  |  |  |
Ark |  | 28.0 | % |  | $ | 397.9 |  | (2) | 28.0 | % |  | $ | 336.9 |  | (2)
HG Global |  | 3.1 | % |  | (9.3) |  |  | 3.1 | % |  | .8 |  |
Kudu |  | 9.9 | % |  | 133.7 |  |  | 10.5 | % |  | 113.8 |  |
Bamboo |  | 27.2 | % |  | 117.6 |  |  | — | % |  | — |  |
Other |  | various |  | 9.3 |  |  | various |  | 9.4 |  |
Total, excluding BAM |  |  |  | 649.2 |  |  |  |  | 460.9 |  |
BAM (3) |  | — | % |  | — |  |  | 100.0 | % |  | (139.8) |  |
Total noncontrolling interests |  |  |  | $ | 649.2 |  |  |  |  | $ | 321.1 |  |
(1) The noncontrolling percentage represents the basic ownership interests held by noncontrolling shareholders with the exception of HG Global, for which the noncontrolling percentage represents the preferred share ownership held by noncontrolling shareholders. (2) As of September 30, 2024 and December 31, 2023, Ark’s noncontrolling equity includes $40.3 and $21.0 related to management’s equity incentives. (3) Effective July 1, 2024, White Mountains no longer consolidates BAM. Through June 30, 2024, BAM’s results are attributed to noncontrolling interests in White Mountains’s consolidated financial statements.

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