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Investments - Schedule of Unrealized Loss on Investments (Details) $ in Thousands | Sep. 30, 2023 USD ($) security | Dec. 31, 2022 USD ($) 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 | 0 | 3
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 105
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 2,385
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 3 | 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 95 | $ 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 2,399 | $ 0
States, Municipalities and Political Subdivisions |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 5 | 21
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 113 | $ 540
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,433 | $ 7,306
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 44 | 31
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 3,232 | $ 3,525
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 19,837 | $ 18,853
Public Utilities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 0 | 8
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 193
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 2,286
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 12 | 4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 692 | $ 1,049
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 4,967 | $ 5,408
Corporate Securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 6 | 78
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 143 | $ 2,279
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,290 | $ 24,594
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 137 | 77
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 11,307 | $ 13,460
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 57,858 | $ 57,765
Mortgage-backed securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 4 | 48
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 77 | $ 1,282
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 908 | $ 15,259
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 119 | 80
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 9,321 | $ 7,854
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 45,220 | $ 40,856
Asset-backed Securities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 5 | 16
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 38 | $ 795
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,135 | $ 6,397
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 43 | 46
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 1,929 | $ 1,993
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 14,053 | $ 19,028
Fixed Maturities |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 20 | 175
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 371 | $ 5,203
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 7,766 | $ 59,218
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 359 | 238
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 26,576 | $ 27,881
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 145,334 | $ 141,910
Foreign Government |  |
Twelve Months or More |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | security | 0 | 1
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 9
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 991
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 1 | 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer | $ 1,000 | $ 0

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