v3.19.3
Liability for Losses and Loss Expenses - Summary of Insurance Subsidiaries' Liability for Losses and Loss Expenses (Detail) - USD ($)
9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Liability for Claims and Claims Adjustment Expense [Abstract]    
Balance at January 1 $ 814,665,224 $ 676,672,000
Less reinsurance recoverable (339,267,000) (293,271,000)
Net balance at January 1 475,398,000 383,401,000
Incurred related to:    
Current year 393,301,000 404,150,000
Prior years (7,940,000) 28,913,000
Total incurred 385,361,000 433,063,000
Paid related to:    
Current year 197,234,000 214,825,000
Prior years 157,691,000 140,806,000
Total paid 354,925,000 355,631,000
Net balance at end of period 505,834,000 460,833,000
Plus reinsurance recoverable 358,700,000 319,147,000
Balance at end of period $ 864,534,338 $ 779,980,000