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Reinsurance (Tables) | 9 Months Ended
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Sep. 30, 2025
Reinsurance Disclosures [Abstract] |
Effect Of Reinsurance And Retrocessional Reinsurance On Premiums Written And Earned | The following tables summarize the effect of reinsurance and retrocessional reinsurance on premiums written and earned. Fronting premiums are attributable to business written on behalf of third-party capacity providers, substantially all of which are ceded.
| Quarter Ended September 30,
| 2025 |  | 2024
(dollars in thousands) | Direct |  | Assumed |  | Ceded |  | Net Premiums |  | Direct |  | Assumed |  | Ceded |  | Net Premiums
Underwriting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 2,420,107 |  |  | $ | 382,313 |  |  | $ | (563,681) |  |  | $ | 2,238,739 |  |  | $ | 2,249,500 |  |  | $ | 282,089 |  |  | $ | (549,264) |  |  | $ | 1,982,325 |
Earned | $ | 2,275,753 |  |  | $ | 453,405 |  |  | $ | (522,939) |  |  | $ | 2,206,219 |  |  | $ | 2,206,453 |  |  | $ | 404,686 |  |  | $ | (500,842) |  |  | $ | 2,110,297 |
Fronting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | 704,379 |  |  | 352,094 |  |  | (1,057,016) |  |  | (543) |  |  | 763,082 |  |  | 177,038 |  |  | (940,309) |  |  | (189) |
Earned | 843,146 |  |  | 1,112,200 |  |  | (1,955,792) |  |  | (446) |  |  | 721,786 |  |  | 530,688 |  |  | (1,252,663) |  |  | (189) |
Consolidated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 3,124,486 |  |  | $ | 734,407 |  |  | $ | (1,620,697) |  |  | $ | 2,238,196 |  |  | $ | 3,012,582 |  |  | $ | 459,127 |  |  | $ | (1,489,573) |  |  | $ | 1,982,136 |
Earned | $ | 3,118,899 |  |  | $ | 1,565,605 |  |  | $ | (2,478,731) |  |  | $ | 2,205,773 |  |  | $ | 2,928,239 |  |  | $ | 935,374 |  |  | $ | (1,753,505) |  |  | $ | 2,110,108 |
| Nine Months Ended September 30,
| 2025 |  | 2024
(dollars in thousands) | Direct |  | Assumed |  | Ceded |  | Net Premiums |  | Direct |  | Assumed |  | Ceded |  | Net Premiums
Underwriting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 6,970,879 |  |  | $ | 1,583,225 |  |  | $ | (1,761,973) |  |  | $ | 6,792,131 |  |  | $ | 6,713,503 |  |  | $ | 1,515,639 |  |  | $ | (1,735,668) |  |  | $ | 6,493,474 |
Earned | $ | 6,681,520 |  |  | $ | 1,342,521 |  |  | $ | (1,587,018) |  |  | $ | 6,437,023 |  |  | $ | 6,554,464 |  |  | $ | 1,212,116 |  |  | $ | (1,451,224) |  |  | $ | 6,315,356 |
Fronting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | 2,299,790 |  |  | 2,367,720 |  |  | (4,667,803) |  |  | (293) |  |  | 2,451,180 |  |  | 1,443,916 |  |  | (3,895,618) |  |  | (522) |
Earned | 2,414,888 |  |  | 1,673,636 |  |  | (4,088,709) |  |  | (185) |  |  | 2,236,845 |  |  | 894,803 |  |  | (3,132,170) |  |  | (522) |
Consolidated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 9,270,669 |  |  | $ | 3,950,945 |  |  | $ | (6,429,776) |  |  | $ | 6,791,838 |  |  | $ | 9,164,683 |  |  | $ | 2,959,555 |  |  | $ | (5,631,286) |  |  | $ | 6,492,952 |
Earned | $ | 9,096,408 |  |  | $ | 3,016,157 |  |  | $ | (5,675,727) |  |  | $ | 6,436,838 |  |  | $ | 8,791,309 |  |  | $ | 2,106,919 |  |  | $ | (4,583,394) |  |  | $ | 6,314,834 |
Percentage of reinsurance ceded earned premiums to GEP & assumed earned premiums to NEP [Table Text Block] |
| Quarter Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Ceded earned premiums to gross earned premiums | 53 | % |  | 45 | % |  | 47 | % |  | 42 | %
Assumed earned premiums to net earned premiums | 71 | % |  | 44 | % |  | 47 | % |  | 33 | %
Effect Of Reinsurance And Retrocessional Reinsurance On Losses and Loss Adjustment Expenses | The following table summarizes the effect of reinsurance and retrocessional reinsurance on losses and loss adjustment expenses in the Company's underwriting operations.
| Quarter Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands) | 2025 |  | 2024 |  | 2025 |  | 2024
Gross losses and loss adjustment expenses | $ | 1,566,985 |  |  | $ | 1,710,637 |  |  | $ | 4,900,250 |  |  | $ | 4,982,304 |
Ceded losses and loss adjustment expenses | (313,061) |  |  | (419,194) |  |  | (1,103,552) |  |  | (1,170,585) |
Net losses and loss adjustment expenses | $ | 1,253,924 |  |  | $ | 1,291,443 |  |  | $ | 3,796,698 |  |  | $ | 3,811,719 |

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