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Investments - Schedule of Unrealized Loss on Investments (Details) $ in Thousands	Sep. 30, 2025 USD ($) Security	Dec. 31, 2024 USD ($) Security
U.S. Government and Agency Securities
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	0	2
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 0	$ 25
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 5,878
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	0	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	$ 0	$ 0
Corporate Securities
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	21	42
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 37	$ 300
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 7,856	$ 14,559
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	81	80
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 4,035	$ 6,195
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 46,733	$ 45,702
Mortgage-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	$ 7	$ 26
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 715	$ 1,244
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	56	61
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 4,196	$ 5,407
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 26,683	$ 29,218
States, Municipalities and Political Subdivisions
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	2	4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 1	$ 25
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 514	$ 1,330
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	24	27
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 1,245	$ 1,882
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 14,912	$ 15,868
Asset-backed Securities
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	3	6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 2	$ 21
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 591	$ 2,104
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	21	22
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 702	$ 885
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 6,788	$ 7,977
Public Utilities
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	2	6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 0	$ 37
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 750	$ 1,937
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	7	6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 202	$ 330
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 3,718	$ 3,347
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	$ 427
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	0	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	$ 0	$ 0
Fixed Maturities
Twelve Months or More
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	31	65
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 47	$ 443
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 10,426	$ 27,479
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Security	189	196
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 10,380	$ 14,699
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 98,834	$ 102,112

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