v3.26.3
Operating Segment Information - Operating Results by Segment (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Revenue        
Net premiums earned $ 424,914 $ 407,695 $ 1,253,396 $ 1,207,944
Net investment income 46,694 41,270 135,057 117,414
Net realized gains 8,637 18,318 27,603 48,234
Net unrealized gains (losses) on equity securities (3,282) 41,981 60,346 43,163
Consolidated revenue 476,963 509,264 1,476,402 1,416,755
Less: Expenses        
Losses and settlement expenses 201,341 187,998 584,480 549,814
Insurance operating expenses 30,657 30,215 91,554 86,683
Earnings before income taxes 100,093 157,245 378,122 392,391
Casualty Segment        
Revenue        
Net premiums earned 262,177 243,508 767,665 707,194
Property Segment        
Revenue        
Net premiums earned 126,520 126,689 376,684 389,897
Surety Segment        
Revenue        
Net premiums earned 36,217 37,498 109,047 110,853
Operating Segments        
Revenue        
Net premiums earned 424,914 407,695 1,253,396 1,207,944
Net investment income 46,694 41,270 135,057 117,414
Net realized gains 8,637 18,318 27,603 48,234
Net unrealized gains (losses) on equity securities (3,282) 41,981 60,346 43,163
Consolidated revenue 476,963 509,264 1,476,402 1,416,755
Less: Expenses        
Earnings before income taxes 58,769 60,545 176,465 193,321
Operating Segments | Casualty Segment        
Revenue        
Net premiums earned 262,177 243,508 767,665 707,194
Consolidated revenue 262,177 243,508 767,665 707,194
Less: Expenses        
Losses and settlement expenses 168,087 150,912 480,605 438,007
Amortization of deferred acquisition costs 51,244 47,335 149,306 135,999
Other policy acquisition costs 23,699 23,199 73,524 67,935
Insurance operating expenses 18,107 17,576 54,155 50,407
Earnings before income taxes 1,040 4,486 10,075 14,846
Depreciation and amortization expense 1,542 1,517 4,698 4,556
Operating Segments | Property Segment        
Revenue        
Net premiums earned 126,520 126,689 376,684 389,897
Consolidated revenue 126,520 126,689 376,684 389,897
Less: Expenses        
Losses and settlement expenses 31,103 32,815 91,682 103,999
Amortization of deferred acquisition costs 25,963 26,311 76,272 79,985
Other policy acquisition costs 10,115 8,219 30,064 23,496
Insurance operating expenses 8,913 8,920 26,556 25,567
Earnings before income taxes 50,426 50,424 152,110 156,850
Depreciation and amortization expense 504 534 1,557 1,553
Operating Segments | Surety Segment        
Revenue        
Net premiums earned 36,217 37,498 109,047 110,853
Consolidated revenue 36,217 37,498 109,047 110,853
Less: Expenses        
Losses and settlement expenses 2,151 4,271 12,193 7,808
Amortization of deferred acquisition costs 12,708 13,103 38,194 38,361
Other policy acquisition costs 10,418 10,770 33,537 32,350
Insurance operating expenses 3,637 3,719 10,843 10,709
Earnings before income taxes 7,303 5,635 14,280 21,625
Depreciation and amortization expense 356 370 1,077 1,039
Corporate        
Revenue        
Net investment income 46,694 41,270 135,057 117,414
Net realized gains 8,637 18,318 27,603 48,234
Net unrealized gains (losses) on equity securities $ (3,282) $ 41,981 $ 60,346 $ 43,163