v3.26.3
Reserve for Losses and Loss Adjustment Expenses - Schedule of Reconciliation of Unpaid Losses and Loss Adjustment Expenses (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]        
Gross unpaid losses and loss adjustment expenses, beginning of period     $ 4,415,176 $ 3,532,491
Reinsurance recoverable on unpaid losses     1,375,857 1,171,040
Net unpaid losses and loss adjustment expenses, beginning of period     3,039,319 2,361,451
Net losses and loss adjustment expenses incurred in respect of losses occurring in:        
Current year     1,015,881 989,729
Prior years     37,119 (45,854)
Total incurred $ 366,726 $ 278,712 1,053,000 943,875
Net losses and loss adjustment expenses paid in respect of losses occurring in:        
Current year     88,957 125,827
Prior years     475,205 321,706
Total paid     564,162 447,533
Foreign currency revaluation and other     (7,820) 44,451
Net unpaid losses and loss adjustment expenses, end of period 3,520,337 2,902,244 3,520,337 2,902,244
Reinsurance recoverable on unpaid losses 1,468,584 1,303,833 1,468,584 1,303,833
Gross unpaid losses and loss adjustment expenses, end of period $ 4,988,921 $ 4,206,077 $ 4,988,921 $ 4,206,077