v3.25.1
Summary of Amortized Cost and Estimated Fair Value Through Fixed Maturities (Detail) - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
Schedule Of Available For Sale Securities [Line Items]    
Due in one year or less, Amortized Cost $ 597,762  
Due in one year through five years, Amortized Cost 284,061  
Due in five years through ten years, Amortized Cost 9,531  
Due after ten years, Amortized Cost 9,858  
Fixed maturities, Amortized Cost 1,323,666 $ 1,394,639
Due in one year or less, Estimated Fair value 597,332  
Due in one year through five years, Estimated Fair value 282,263  
Due in five years through ten years, Estimated Fair value 8,834  
Due after ten years, Estimated Fair value 9,077  
Fixed Maturities, estimated fair value 1,315,399 1,381,908
Mortgage Backed Securities    
Schedule Of Available For Sale Securities [Line Items]    
Amortized Cost 210,360  
Fixed maturities, Amortized Cost 210,360 61,905
Estimated Fair value 208,636  
Fixed Maturities, estimated fair value 208,636 58,920
Asset-backed Securities    
Schedule Of Available For Sale Securities [Line Items]    
Amortized Cost 143,084  
Fixed maturities, Amortized Cost 143,084 137,445
Estimated Fair value 141,700  
Fixed Maturities, estimated fair value 141,700 135,427
Commercial Mortgage-Backed Securities    
Schedule Of Available For Sale Securities [Line Items]    
Amortized Cost 69,010  
Fixed maturities, Amortized Cost 69,010 68,041
Estimated Fair value 67,557  
Fixed Maturities, estimated fair value $ 67,557 $ 65,568