v3.26.1
Investments - Summary of Amortized Cost, Allowance for Credit Loss, Gross Unrealized Gains and Losses, and Estimated Fair Value of Available-for-Sale Securities (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Schedule of Available-for-sale Securities [Line Items]    
Fixed-maturity securities, Cost or Amortized Cost $ 1,103,778 $ 595,383
Allowance for Credit Loss 0 0
Fixed-maturity securities, Gross Unrealized Gains 223 3,322
Fixed-maturity securities, Gross Unrealized Losses (12,960) (1,376)
Fixed-maturity securities, available-for-sale, at fair value [1] 1,091,041 597,329
U.S. Treasury and U.S. Government Agencies [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Allowance for Credit Loss 0 0
Corporate Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Allowance for Credit Loss 0 0
Commercial Mortgage Backed Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Allowance for Credit Loss 0 0
Fixed-Maturity Securities [Member] | U.S. Treasury and U.S. Government Agencies [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Fixed-maturity securities, Cost or Amortized Cost 835,084 332,284
Fixed-maturity securities, Gross Unrealized Gains 122 1,785
Fixed-maturity securities, Gross Unrealized Losses (10,902) (717)
Fixed-maturity securities, available-for-sale, at fair value 824,304 333,352
Fixed-Maturity Securities [Member] | Corporate Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Fixed-maturity securities, Cost or Amortized Cost 242,419 241,843
Fixed-maturity securities, Gross Unrealized Gains 52 1,463
Fixed-maturity securities, Gross Unrealized Losses (1,720) (384)
Fixed-maturity securities, available-for-sale, at fair value 240,751 242,922
Fixed-Maturity Securities [Member] | Commercial Mortgage Backed Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Fixed-maturity securities, Cost or Amortized Cost 26,275 21,256
Fixed-maturity securities, Gross Unrealized Gains 49 74
Fixed-maturity securities, Gross Unrealized Losses (338) (275)
Fixed-maturity securities, available-for-sale, at fair value $ 25,986 $ 21,055
[1] See Note 12 for details of balances associated with consolidated variable interest entities.