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Fixed Maturity Securities in an Unrealized Loss Position (Tables) | 12 Months Ended
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Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract] |
Securities In An Unrealized Loss Position | The following tables summarize all fixed maturity securities in an unrealized loss position at December 31, 2024 and 2023 by the length of time those securities have been continuously in an unrealized loss position.
| Less Than 12 Months |  | 12 Months or Greater |  | Total
(In thousands) | Fair Value |  | Gross Unrealized Losses |  | Fair Value |  | Gross Unrealized Losses |  | Fair Value |  | Gross Unrealized Losses
December 31, 2024 |  |  |  |  |  |  |  |  |  |  |
U.S. government and government agency | $ | 767,515 |  |  | $ | 9,637 |  |  | $ | 560,260 |  |  | $ | 33,226 |  |  | $ | 1,327,775 |  |  | $ | 42,863 |
State and municipal | 348,116 |  |  | 8,027 |  |  | 1,411,761 |  |  | 81,430 |  |  | 1,759,877 |  |  | 89,457 |
Mortgage-backed securities | 1,541,464 |  |  | 21,326 |  |  | 1,060,823 |  |  | 171,734 |  |  | 2,602,287 |  |  | 193,060 |
Asset-backed securities | 411,763 |  |  | 4,613 |  |  | 626,237 |  |  | 36,899 |  |  | 1,038,000 |  |  | 41,512 |
Corporate | 1,791,970 |  |  | 21,346 |  |  | 2,951,377 |  |  | 135,117 |  |  | 4,743,347 |  |  | 156,463 |
Foreign government | 600,103 |  |  | 17,933 |  |  | 476,479 |  |  | 167,440 |  |  | 1,076,582 |  |  | 185,373 |
Fixed maturity securities | $ | 5,460,931 |  |  | $ | 82,882 |  |  | $ | 7,086,937 |  |  | $ | 625,846 |  |  | $ | 12,547,868 |  |  | $ | 708,728 |
December 31, 2023 |  |  |  |  |  |  |  |  |  |  |
U.S. government and government agency | $ | 384,392 |  |  | $ | 6,655 |  |  | $ | 614,623 |  |  | $ | 51,014 |  |  | $ | 999,015 |  |  | $ | 57,669 |
State and municipal | 264,273 |  |  | 3,013 |  |  | 1,680,034 |  |  | 119,449 |  |  | 1,944,307 |  |  | 122,462 |
Mortgage-backed securities | 278,819 |  |  | 2,025 |  |  | 1,360,748 |  |  | 175,131 |  |  | 1,639,567 |  |  | 177,156 |
Asset-backed securities | 413,511 |  |  | 2,070 |  |  | 2,176,035 |  |  | 71,136 |  |  | 2,589,546 |  |  | 73,206 |
Corporate | 874,754 |  |  | 11,975 |  |  | 4,418,309 |  |  | 231,288 |  |  | 5,293,063 |  |  | 243,263 |
Foreign government | 204,908 |  |  | 1,758 |  |  | 794,174 |  |  | 135,661 |  |  | 999,082 |  |  | 137,419 |
Fixed maturity securities | $ | 2,420,657 |  |  | $ | 27,496 |  |  | $ | 11,043,923 |  |  | $ | 783,679 |  |  | $ | 13,464,580 |  |  | $ | 811,175 |
Non-Investment Grade Fixed Maturity Securities | A summary of the Company’s non-investment grade fixed maturity securities that were in an unrealized loss position at December 31, 2024 is presented in the table below:
($ in thousands) | Number of Securities |  | Aggregate Fair Value |  | Gross Unrealized Loss
Foreign government | 50 |  |  | $ | 138,388 |  |  | $ | 157,424 |
Corporate | 19 |  |  | 50,525 |  |  | 2,922 |
State and municipal | 6 |  |  | 28,150 |  |  | 1,921 |
Mortgage-backed securities | 17 |  |  | 3,684 |  |  | 206 |
Asset-backed securities | 1 |  |  | 9 |  |  | 1 |
Total | 93 |  |  | $ | 220,756 |  |  | $ | 162,474 |

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