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Fixed Maturity Securities in an Unrealized Loss Position | 12 Months Ended
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Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract] |
Fixed Maturity Securities in an Unrealized Loss Position | Fixed Maturity Securities in an Unrealized Loss Position The following tables summarize all fixed maturity securities in an unrealized loss position at December 31, 2023 and 2022 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, 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 |
December 31, 2022 |  |  |  |  |  |  |  |  |  |  |
U.S. government and government agency | $ | 285,391 |  |  | $ | 10,219 |  |  | $ | 453,520 |  |  | $ | 58,939 |  |  | $ | 738,911 |  |  | $ | 69,158 |
State and municipal | 1,720,443 |  |  | 89,272 |  |  | 598,797 |  |  | 79,320 |  |  | 2,319,240 |  |  | 168,592 |
Mortgage-backed securities | 1,099,549 |  |  | 75,430 |  |  | 473,318 |  |  | 115,528 |  |  | 1,572,867 |  |  | 190,958 |
Asset-backed securities | 1,569,647 |  |  | 48,390 |  |  | 2,176,638 |  |  | 103,932 |  |  | 3,746,285 |  |  | 152,322 |
Corporate | 3,690,856 |  |  | 150,115 |  |  | 2,349,281 |  |  | 256,631 |  |  | 6,040,137 |  |  | 406,746 |
Foreign government | 477,672 |  |  | 29,815 |  |  | 711,786 |  |  | 105,243 |  |  | 1,189,458 |  |  | 135,058 |
Fixed maturity securities | $ | 8,843,558 |  |  | $ | 403,241 |  |  | $ | 6,763,340 |  |  | $ | 719,593 |  |  | $ | 15,606,898 |  |  | $ | 1,122,834 |
Substantially all of the securities in an unrealized loss position are rated investment grade, except for the securities in the foreign government classification. A significant amount of the unrealized loss on foreign government securities is the result of changes in currency exchange rates. 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, 2023 is presented in the table below:
($ in thousands) | Number of Securities |  | Aggregate Fair Value |  | Gross Unrealized Loss
Foreign government | 33 |  |  | $ | 102,689 |  |  | $ | 107,301 |
State and municipal | 5 |  |  | 22,830 |  |  | 6,469 |
Corporate | 16 |  |  | 21,424 |  |  | 1,928 |
Mortgage-backed securities | 15 |  |  | 4,393 |  |  | 185 |
Asset-backed securities | 5 |  |  | 197 |  |  | 148 |
Total | 74 |  |  | $ | 151,533 |  |  | $ | 116,031 |
For fixed maturity securities that management does not intend to sell or to be required to sell, the portion of the decline in value that is considered to be due to credit factors is recognized in earnings, and the portion of the decline in value that is considered to be due to non-credit factors is recognized in other comprehensive income. The Company has evaluated its fixed maturity securities in an unrealized loss position and believes the unrealized losses are due primarily to temporary market and sector-related factors rather than to issuer-specific factors. None of these securities are delinquent or in default under financial covenants. Based on its assessment of these issuers, the Company expects them to continue to meet their contractual payment obligations as they become due.

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