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Municipal Bond Guarantee Reinsurance - Schedule of Net Written Premiums (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Written premiums: |  |  |  |
Direct |  | $ 24.1 | $ 58.6 | $ 63.8
Assumed |  | 31.9 | 0.0 | 1.3
Gross written premiums |  | 56.0 | 58.6 | 65.1
Earned premiums: |  |  |  |
Direct |  | 15.8 | 28.7 | 28.6
Assumed Premiums Earned |  | 15.9 | 2.5 | 4.7
Gross earned premiums |  | 31.7 | 31.2 | 33.3
HG Global |  |  |  |
Written premiums: |  |  |  |
Direct |  | 0.0 | 0.0 | 0.0
Assumed |  | 52.4 | 50.1 | 55.9
Gross written premiums |  | 52.4 | 50.1 | 55.9
Earned premiums: |  |  |  |
Direct |  | 0.0 | 0.0 | 0.0
Assumed Premiums Earned |  | 28.9 | 26.0 | 27.5
Gross earned premiums |  | 28.9 | 26.0 | 27.5
BAM |  |  |  |
Written premiums: |  |  |  |
Direct |  | 24.1 | 58.6 | 63.8
Assumed |  | 0.0 | 0.0 | 1.3
Gross written premiums |  | 24.1 | 58.6 | 65.1
Earned premiums: |  |  |  |
Direct |  | 15.8 | 28.7 | 28.6
Assumed Premiums Earned |  | 1.0 | 2.5 | 4.7
Gross earned premiums |  | 16.8 | 31.2 | 33.3
Ceded Premiums Written | $ (20.5) |  | (50.1) | (55.9)
Ceded to Other Companies | $ (14.0) |  | (26.0) | (27.5)
Eliminations |  |  |  |
Written premiums: |  |  |  |
Direct |  | 0.0 | 0.0 | 0.0
Assumed |  | (20.5) | (50.1) | (55.9)
Gross written premiums |  | (20.5) | (50.1) | (55.9)
Earned premiums: |  |  |  |
Direct |  | 0.0 | 0.0 | 0.0
Assumed Premiums Earned |  | (14.0) | (26.0) | (27.5)
Gross earned premiums |  | $ (14.0) | $ (26.0) | $ (27.5)

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