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SCHEDULE IV - REINSURANCE | 12 Months Ended
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Dec. 31, 2023
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] |
SCHEDULE IV - REINSURANCE | WHITE MOUNTAINS INSURANCE GROUP, LTD. REINSURANCE
Column A |  | Column B |  | Column C |  | Column D |  | Column E |  | Column F
$ in Millions Premiums Earned |  | Gross Amount |  | Ceded to Other Companies |  | Assumed from Other Companies |  | Net Amount |  | Percentage of Amount Assumed to Net
Year ended: |  |  |  |  |  |  |  |  |  |
December 31, 2023 |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | $ | 28.7 |  |  | $ | — |  |  | $ | 2.5 |  |  | $ | 31.2 |  |  | 8.0 | %
Ark/WM Outrigger |  | 848.1 |  |  | (364.0) |  |  | 925.6 |  |  | 1,409.7 |  |  | 65.7 |
December 31, 2022 |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | 28.6 |  |  | — |  |  | 4.7 |  |  | 33.3 |  |  | 14.1 |
Ark/WM Outrigger |  | 655.5 |  |  | (280.8) |  |  | 668.7 |  |  | 1,043.4 |  |  | 64.1 |
December 31, 2021 |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | 23.2 |  |  | — |  |  | 3.7 |  |  | 26.9 |  |  | 13.8 |
Ark/WM Outrigger |  | 556.0 |  |  | (249.1) |  |  | 330.4 |  |  | 637.3 |  |  | 51.8 |
Schedules of the Registrant should be read in conjunction with the Consolidated Financial Statements and Notes.

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- References No definition available. + Details
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- Definition The entire disclosure for the supplemental schedule of reinsurance information. Reinsurance schedule includes, but is not limited to, the type of insurance, gross amount of premiums, premiums ceded to other entities, premiums assumed from other entities, net amount of premium revenue, and the percentage of the premiums assumed to net premium revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-X (SX) -Number 210 -Section 12 -Subsection 17 -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2 + Details
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