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Reinsurance (Tables) | 6 Months Ended
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Jun. 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 June 30,
| 2025 |  | 2024
(dollars in thousands) | Direct |  | Assumed |  | Ceded |  | Net Premiums |  | Direct |  | Assumed |  | Ceded |  | Net Premiums
Underwriting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 2,414,799 |  |  | $ | 471,869 |  |  | $ | (643,567) |  |  | $ | 2,243,101 |  |  | $ | 2,356,536 |  |  | $ | 564,851 |  |  | $ | (642,448) |  |  | $ | 2,278,939 |
Earned | $ | 2,210,284 |  |  | $ | 451,071 |  |  | $ | (519,923) |  |  | $ | 2,141,432 |  |  | $ | 2,149,773 |  |  | $ | 414,488 |  |  | $ | (487,002) |  |  | $ | 2,077,259 |
Fronting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | 821,727 |  |  | 1,436,096 |  |  | (2,257,573) |  |  | 250 |  |  | 943,140 |  |  | 847,603 |  |  | (1,790,903) |  |  | (160) |
Earned | 832,497 |  |  | 317,130 |  |  | (1,149,368) |  |  | 259 |  |  | 811,377 |  |  | 240,844 |  |  | (1,052,381) |  |  | (160) |
Consolidated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 3,236,526 |  |  | $ | 1,907,965 |  |  | $ | (2,901,140) |  |  | $ | 2,243,351 |  |  | $ | 3,299,676 |  |  | $ | 1,412,454 |  |  | $ | (2,433,351) |  |  | $ | 2,278,779 |
Earned | $ | 3,042,781 |  |  | $ | 768,201 |  |  | $ | (1,669,291) |  |  | $ | 2,141,691 |  |  | $ | 2,961,150 |  |  | $ | 655,332 |  |  | $ | (1,539,383) |  |  | $ | 2,077,099 |
| Six Months Ended June 30,
| 2025 |  | 2024
(dollars in thousands) | Direct |  | Assumed |  | Ceded |  | Net Premiums |  | Direct |  | Assumed |  | Ceded |  | Net Premiums
Underwriting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 4,550,772 |  |  | $ | 1,200,912 |  |  | $ | (1,198,292) |  |  | $ | 4,553,392 |  |  | $ | 4,464,003 |  |  | $ | 1,233,550 |  |  | $ | (1,186,404) |  |  | $ | 4,511,149 |
Earned | $ | 4,405,767 |  |  | $ | 889,116 |  |  | $ | (1,064,079) |  |  | $ | 4,230,804 |  |  | $ | 4,348,011 |  |  | $ | 807,430 |  |  | $ | (950,382) |  |  | $ | 4,205,059 |
Fronting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | 1,595,411 |  |  | 2,015,626 |  |  | (3,610,787) |  |  | 250 |  |  | 1,688,098 |  |  | 1,266,878 |  |  | (2,955,309) |  |  | (333) |
Earned | 1,571,742 |  |  | 561,436 |  |  | (2,132,917) |  |  | 261 |  |  | 1,515,059 |  |  | 364,115 |  |  | (1,879,507) |  |  | (333) |
Consolidated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Written | $ | 6,146,183 |  |  | $ | 3,216,538 |  |  | $ | (4,809,079) |  |  | $ | 4,553,642 |  |  | $ | 6,152,101 |  |  | $ | 2,500,428 |  |  | $ | (4,141,713) |  |  | $ | 4,510,816 |
Earned | $ | 5,977,509 |  |  | $ | 1,450,552 |  |  | $ | (3,196,996) |  |  | $ | 4,231,065 |  |  | $ | 5,863,070 |  |  | $ | 1,171,545 |  |  | $ | (2,829,889) |  |  | $ | 4,204,726 |
Percentage of reinsurance ceded earned premiums to GEP & assumed earned premiums to NEP [Table Text Block] |
| Quarter Ended June 30, |  | Six Months Ended June 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Ceded earned premiums to gross earned premiums | 44 | % |  | 43 | % |  | 43 | % |  | 40 | %
Assumed earned premiums to net earned premiums | 36 | % |  | 32 | % |  | 34 | % |  | 28 | %
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 June 30, |  | Six Months Ended June 30,
(dollars in thousands) | 2025 |  | 2024 |  | 2025 |  | 2024
Gross losses and loss adjustment expenses | $ | 1,659,756 |  |  | $ | 1,577,820 |  |  | $ | 3,333,265 |  |  | $ | 3,271,667 |
Ceded losses and loss adjustment expenses | (371,564) |  |  | (345,224) |  |  | (790,491) |  |  | (751,391) |
Net losses and loss adjustment expenses | $ | 1,288,192 |  |  | $ | 1,232,596 |  |  | $ | 2,542,774 |  |  | $ | 2,520,276 |

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