Fair Value of Financial Instruments - Level 1 - 3 Inputs (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair value of financial instruments
Total investment securities	$ 1,315,548	$ 1,115,218
Fixed maturity securities, Estimated Fair Value	1,315,548	1,115,218
Equity securities, Estimated Fair Value	220,953	221,422
Total
Fair value of financial instruments
Total investment securities	1,518,711	1,339,338
Total \| U.S. Treasury securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	4,205	2,343
Total \| Obligations of states and political subdivisions
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	37,718	36,166
Total \| Residential mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	366,047	301,227
Total \| Commercial mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	157,018	129,375
Total \| Other asset-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	169,509	63,717
Total \| Corporate and other securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	581,051	582,390
Total \| Short term investments
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	0	19,975
Total \| Other invested assets
Fair value of financial instruments
Equity securities, Estimated Fair Value	14,209	14,477
Total \| Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	188,954	189,668
Level 1 Inputs
Fair value of financial instruments
Total investment securities	188,022	187,548
Level 1 Inputs \| Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	188,022	187,548
Level 2 Inputs
Fair value of financial instruments
Total investment securities	1,329,757	1,149,670
Level 2 Inputs \| U.S. Treasury securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	4,205	2,343
Level 2 Inputs \| Obligations of states and political subdivisions
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	37,718	36,166
Level 2 Inputs \| Residential mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	366,047	301,227
Level 2 Inputs \| Commercial mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	157,018	129,375
Level 2 Inputs \| Other asset-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	169,509	63,717
Level 2 Inputs \| Corporate and other securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	581,051	582,390
Level 2 Inputs \| Short term investments
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value		19,975
Level 2 Inputs \| Other invested assets
Fair value of financial instruments
Equity securities, Estimated Fair Value	14,209	14,477
Level 3 Inputs
Fair value of financial instruments
Total investment securities	932	2,120
Level 3 Inputs \| Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	$ 932	$ 2,120

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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