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Investments - Schedule of Unrealized Loss on Investments (Details) $ in Thousands | Mar. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) security
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U.S. Government and Agency Securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 14 | 9
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 131 | $ 14
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 25,867 | $ 19,943
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 2 | 2
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 67 | $ 54
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 1,428 | $ 1,430
States, Municipalities and Political Subdivisions |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 5 | 4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 39 | $ 12
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,508 | $ 2,052
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 44 | 44
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 2,490 | $ 2,468
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 20,519 | $ 20,571
Public Utilities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 0 | 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 12 | 12
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 504 | $ 511
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 5,128 | $ 5,134
Corporate Securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 1 | 3
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 2 | $ 27
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 598 | $ 1,255
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 136 | 133
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 8,560 | $ 8,341
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 60,311 | $ 59,419
Mortgage-backed securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 2 | 2
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 29 | $ 14
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 783 | $ 807
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 114 | 117
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 7,158 | $ 7,295
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 43,756 | $ 45,502
Asset-backed Securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 3 | 4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 12 | $ 6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 1,136 | $ 1,354
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 43 | 43
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 1,453 | $ 1,555
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 13,844 | $ 14,074
Fixed Maturities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 25 | 22
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 213 | $ 73
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 30,892 | $ 25,411
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 351 | 351
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 20,232 | $ 20,224
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 144,986 | $ 146,130

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