Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	$ 1,404,774	$ 1,189,733
Equity securities:
Bank loan participations	155,138	142,410
Short-term investments	0	97,074
Fair Value, Recurring
Equity securities:
Bank loan participations	155,138	142,410
Short-term investments	0	97,074
Fixed maturity securities
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	1,404,774	1,189,733
Fixed maturity securities | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	1,404,774	1,189,733
State and municipal
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	219,477	196,564
State and municipal | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	219,477	196,564
Residential mortgage-backed
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	472,718	326,227
Residential mortgage-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	472,718	326,227
Corporate
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	577,754	475,485
Corporate | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	577,754	475,485
Commercial mortgage and asset-backed
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	120,535	170,458
Commercial mortgage and asset-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	120,535	170,458
U.S. Treasury securities and obligations guaranteed by the U.S. government
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	14,290	20,999
U.S. Treasury securities and obligations guaranteed by the U.S. government | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	14,290	20,999
Equity securities | Fair Value, Recurring
Equity securities:
Equity securities	73,092	86,479
Preferred stock | Fair Value, Recurring
Equity securities:
Equity securities	70,601	71,245
Common stock | Fair Value, Recurring
Equity securities:
Equity securities	2,491	15,234
Quoted Prices in Active Markets for Identical Assets Level 1 | Fair Value, Recurring
Equity securities:
Bank loan participations	0	0
Short-term investments	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | Fixed maturity securities | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	14,290	20,999
Quoted Prices in Active Markets for Identical Assets Level 1 | State and municipal | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | Residential mortgage-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | Corporate | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | Commercial mortgage and asset-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | U.S. Treasury securities and obligations guaranteed by the U.S. government | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	14,290	20,999
Quoted Prices in Active Markets for Identical Assets Level 1 | Equity securities | Fair Value, Recurring
Equity securities:
Equity securities	0	12,693
Quoted Prices in Active Markets for Identical Assets Level 1 | Preferred stock | Fair Value, Recurring
Equity securities:
Equity securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 | Common stock | Fair Value, Recurring
Equity securities:
Equity securities	0	12,693
Significant Other Observable Inputs Level 2 | Fair Value, Recurring
Equity securities:
Bank loan participations	155,138	142,410
Short-term investments	0	97,074
Significant Other Observable Inputs Level 2 | Fixed maturity securities | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	1,390,484	1,168,734
Significant Other Observable Inputs Level 2 | State and municipal | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	219,477	196,564
Significant Other Observable Inputs Level 2 | Residential mortgage-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	472,718	326,227
Significant Other Observable Inputs Level 2 | Corporate | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	577,754	475,485
Significant Other Observable Inputs Level 2 | Commercial mortgage and asset-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	120,535	170,458
Significant Other Observable Inputs Level 2 | U.S. Treasury securities and obligations guaranteed by the U.S. government | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Other Observable Inputs Level 2 | Equity securities | Fair Value, Recurring
Equity securities:
Equity securities	73,088	73,781
Significant Other Observable Inputs Level 2 | Preferred stock | Fair Value, Recurring
Equity securities:
Equity securities	70,601	71,245
Significant Other Observable Inputs Level 2 | Common stock | Fair Value, Recurring
Equity securities:
Equity securities	2,487	2,536
Significant Unobservable Inputs Level 3 | Fair Value, Recurring
Equity securities:
Bank loan participations	0	0
Short-term investments	0	0
Significant Unobservable Inputs Level 3 | Fixed maturity securities | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | State and municipal | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | Residential mortgage-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | Corporate | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | Commercial mortgage and asset-backed | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | U.S. Treasury securities and obligations guaranteed by the U.S. government | Fair Value, Recurring
Fixed maturity securities, available-for-sale:
Fixed maturity securities, available-for-sale	0	0
Significant Unobservable Inputs Level 3 | Equity securities | Fair Value, Recurring
Equity securities:
Equity securities	4	5
Significant Unobservable Inputs Level 3 | Preferred stock | Fair Value, Recurring
Equity securities:
Equity securities	0	0
Significant Unobservable Inputs Level 3 | Common stock | Fair Value, Recurring
Equity securities:
Equity securities	$ 4	$ 5