Investments - Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Amortized Cost
Due in one year or less, Amortized Cost	$ 7,477
Due after one year through five years, Amortized Cost	303,371
Due after five years through ten years, Amortized Cost	296,277
Due after ten years through twenty years, Amortized Cost	19,835
Due after twenty years, Amortized Cost	834
Asset-backed securities, Amortized Cost	709,441
Totals, Amortized Cost	1,337,235	$ 1,181,038
Estimated Fair Value
Due in one year or less, Estimated Fair Value	7,451
Due after one year through five years, Estimated Fair Value	299,617
Due after five years through ten years, Estimated Fair Value	295,111
Due after ten years through twenty years, Estimated Fair Value	19,929
Due after twenty years, Estimated Fair Value	866
Asset-backed securities, Estimated Fair Value	692,574
Totals, Estimated Fair Value	$ 1,315,548	$ 1,115,218