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Municipal Bond Guarantee Insurance (Tables) | 12 Months Ended
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Dec. 31, 2023
Insurance [Abstract] |
Schedule of insured obligations | The following table presents a schedule of BAM’s insured obligations as of December 31, 2023 and 2022:
|  | December 31,
|  | 2023 |  | 2022
Contracts outstanding |  | 14,485 |  | 13,382
Remaining weighted average contract period (in years) |  | 11.1 |  | 10.8
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 109,673.8 |  |  | $ | 99,996.9 |
Interest |  | 56,012.2 |  |  | 48,880.6 |
Total debt service outstanding |  | $ | 165,686.0 |  |  | $ | 148,877.5 |
Gross unearned insurance premiums (in millions) |  | $ | 325.8 |  |  | $ | 298.3 |
Schedule of BAM’s future premium revenues | The following table presents a schedule of BAM’s future premium revenues as of December 31, 2023:
Millions |  | December 31, 2023
January 1, 2024 - March 31, 2024 |  | $ | 7.5 |
April 1, 2024 - June 30, 2024 |  | 7.5 |
July 1, 2024 - September 30, 2024 |  | 7.3 |
October 1, 2024 - December 31, 2024 |  | 7.2 |
|  | 29.5 |
2025 |  | 27.7 |
2026 |  | 26.0 |
2027 |  | 24.4 |
2028 |  | 22.6 |
2029 and thereafter |  | 195.6 |
Total gross unearned insurance premiums |  | $ | 325.8 |
Effects of reinsurance | The following table summarizes the effects of reinsurance on written and earned premiums and on losses and LAE for the Ark/WM Outrigger segment for the years ended December 31, 2023, 2022 and 2021.
|  | Year Ended December 31,
Millions |  | 2023 |  | 2022 |  | 2021
Written premiums: |  |  |  |  |  |
Direct |  | $ | 931.9 |  |  | $ | 760.4 |  |  | $ | 619.5 |
Assumed |  | 966.5 |  |  | 691.6 |  |  | 439.2 |
Gross written premiums |  | 1,898.4 |  |  | 1,452.0 |  |  | 1,058.7 |
Ceded |  | (377.5) |  | (1) | (256.8) |  |  | (199.6) |
Net written premiums |  | $ | 1,520.9 |  |  | $ | 1,195.2 |  |  | $ | 859.1 |
Earned premiums: |  |  |  |  |  |
Direct |  | $ | 848.1 |  |  | $ | 655.5 |  |  | $ | 556.0 |
Assumed |  | 925.6 |  |  | 668.7 |  |  | 330.4 |
Gross earned premiums |  | 1,773.7 |  |  | 1,324.2 |  |  | 886.4 |
Ceded |  | (364.0) |  | (2) | (280.8) |  |  | (249.1) |
Net earned premiums |  | $ | 1,409.7 |  |  | $ | 1,043.4 |  |  | $ | 637.3 |
Losses and LAE: |  |  |  |  |  |
Gross |  | $ | 782.5 |  |  | $ | 814.9 |  |  | $ | 442.9 |
Ceded |  | (55.7) |  | (3) | (278.5) |  |  | (128.1) |
Net losses and LAE |  | $ | 726.8 |  |  | $ | 536.4 |  |  | $ | 314.8 |
(1) The ceded written premiums exclude $110.0 ceded by Ark to WM Outrigger Re for the year ended December 31, 2023, which eliminate in White Mountains’s consolidated financial statements. (2) The ceded earned premiums exclude $104.3 ceded by Ark to WM Outrigger Re for the year ended December 31, 2023, which eliminate in White Mountains’s consolidated financial statements. (3) The ceded loss and LAE exclude $15.6 ceded by Ark to WM Outrigger Re for the year ended December 31, 2023, which eliminate in White Mountains’s consolidated financial statements. The following table presents the Ark/WM Outrigger segment’s reinsurance recoverables as of December 31, 2023 and December 31, 2022:
Millions |  | December 31, 2023 |  | December 31, 2022 |
Reinsurance recoverables on unpaid losses |  | $ | 340.8 |  | (1) | $ | 505.0 |  | (3)
Reinsurance recoverables on paid losses |  | 27.4 |  |  | 31.1 |  |
Ceded unearned premiums |  | 73.8 |  | (2) | 59.2 |  |
Reinsurance recoverables |  | $ | 442.0 |  |  | $ | 595.3 |  |
(1) The reinsurance recoverables on unpaid losses exclude $15.6 ceded by Ark to WM Outrigger Re as of December 31, 2023, which eliminate in White Mountains’s consolidated financial statements. (2) The ceded unearned premiums exclude $5.7 ceded by Ark to WM Outrigger Re as of December 31, 2023, which eliminate in White Mountains’s consolidated financial statements. (3) The reinsurance recoverables on unpaid losses include $145.4 attributable to TPC Providers as of December 31, 2022, which are collateralized. The following table presents a schedule of written premiums and earned premiums included in the HG Global/BAM segment for the years ended December 31, 2023, 2022 and 2021:
|  | December 31,
Millions |  | 2023 |  | 2022 |  | 2021
Written premiums: |  |  |  |  |  |
Direct |  | $ | 58.6 |  |  | $ | 63.8 |  |  | $ | 51.0 |
Assumed |  | — |  |  | 1.3 |  |  | 4.6 |
Gross written premiums (1) |  | $ | 58.6 |  |  | $ | 65.1 |  |  | $ | 55.6 |
Earned premiums: |  |  |  |  |  |
Direct |  | $ | 28.7 |  |  | $ | 28.6 |  |  | $ | 23.2 |
Assumed |  | 2.5 |  |  | 4.7 |  |  | 3.7 |
Gross earned premiums (1) |  | $ | 31.2 |  |  | $ | 33.3 |  |  | $ | 26.9 |
(1) There are no ceded premium amounts in the periods presented, and gross earned premiums are equivalent to net written premiums and net earned premiums.

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