v3.26.1
Investments - Schedule of Changes in Assets Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3) (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Percent of total fixed maturities 100.00%   100.00%
Significant Unobservable Inputs (Level 3)      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Beginning Balance $ 395,225 $ 474,114  
Included in realized gains / losses 757 (1)  
Included in other comprehensive income (1,964) (1,924)  
Acquisitions 26,449 21,580  
Sales (4,480) 0  
Amortization (1) 1,133  
Other (2,882) (3,468)  
Transfers into Level 3 0 0  
Transfers out of Level 3 0 0  
Ending Balance $ 413,104 $ 491,434  
Percent of total fixed maturities 2.00% 3.00% 2.00%
Significant Unobservable Inputs (Level 3) | Asset- backed Securities      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Beginning Balance $ 85,901 $ 11,183  
Included in realized gains / losses 0 0  
Included in other comprehensive income 251 30  
Acquisitions 13,472 12,380  
Sales 0 0  
Amortization 0 0  
Other 0 0  
Transfers into Level 3 0 0  
Transfers out of Level 3 0 0  
Ending Balance $ 99,624 $ 23,593  
Percent of total fixed maturities 0.00% 0.00%  
Significant Unobservable Inputs (Level 3) | Collateralized debt obligations      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Beginning Balance $ 0 $ 42,866  
Included in realized gains / losses 0 0  
Included in other comprehensive income 0 5,046  
Acquisitions 0 0  
Sales 0 0  
Amortization 0 1,136  
Other 0 (7,393)  
Transfers into Level 3 0 0  
Transfers out of Level 3 0 0  
Ending Balance $ 0 $ 41,655  
Percent of total fixed maturities 0.00% 0.00%  
Significant Unobservable Inputs (Level 3) | States, municipalities, and political subdivisions      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Beginning Balance $ 0 $ 0  
Included in realized gains / losses 0 0  
Included in other comprehensive income 0 0  
Acquisitions 2,977 0  
Sales 0 0  
Amortization 0 0  
Other 0 0  
Transfers into Level 3 0 0  
Transfers out of Level 3 0 0  
Ending Balance $ 2,977 $ 0  
Percent of total fixed maturities 0.00% 0.00%  
Significant Unobservable Inputs (Level 3) | Corporates      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation      
Beginning Balance $ 309,324 $ 420,065  
Included in realized gains / losses 757 (1)  
Included in other comprehensive income (2,215) (7,000)  
Acquisitions 10,000 9,200  
Sales (4,480) 0  
Amortization (1) (3)  
Other (2,882) 3,925  
Transfers into Level 3 0 0  
Transfers out of Level 3 0 0  
Ending Balance $ 310,503 $ 426,186  
Percent of total fixed maturities 2.00% 3.00%