v3.26.1
Investments - Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, Classified as Available-for-Sale (Detail) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Schedule Of Available For Sale Securities [Line Items]    
Within one year, Amortized Cost $ 28,846 $ 41,029
After one year through five years, Amortized Cost 89,171 76,260
After five years through ten years, Amortized Cost 74,422 76,895
After ten years, Amortized Cost $ 125,062 $ 118,986
Investment, Type [Extensible Enumeration] Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Without single maturity date, Amortized Cost $ 3,811 $ 3,946
Available-for-sale, Amortized Cost 321,312 317,116
Within one year, Fair Value 28,781 40,939
After one year through five years, Fair Value 87,825 75,796
After five years through ten years, Fair Value 73,244 76,076
After ten years, Fair Value 120,867 116,586
Without single maturity date, Fair value 3,494 3,641
Available-for-sale, Fair Value $ 314,211 $ 313,038