v3.25.1
Summary of Business Segment Information (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Dec. 31, 2024
Revenues:      
Gross written premiums $ 98,675 $ 93,488  
Net written premiums 95,864 92,085  
Net earned premiums 93,316 96,579  
Net losses and loss adjustment expenses 66,738 53,384  
Net investment income 14,782 14,520  
Net realized investment gains 136 847  
Total revenues 108,651 112,291  
Corporate expenses (9,500) (6,373)  
Income (loss) before income taxes (5,094) 14,265  
Income tax expense (benefit) (1,105) 2,899  
Net income (loss) (3,989) 11,366  
Total assets 1,713,606 1,728,242 $ 1,731,253
Segment assets      
Revenues:      
Gross written premiums 98,675 93,488  
Net written premiums 95,864 92,085  
Net earned premiums 93,316 96,579  
Commission and service fee income 0 [1] 0  
Policy and installment fee income 417 345  
Total segment revenues 93,733 96,924  
Net losses and loss adjustment expenses 66,738 [2] 53,384 [3]  
Net commission expenses 22,334 [2] 23,423 [3]  
Other underwriting expenses 15,173 [2],[4] 14,846 [3],[5]  
Income (loss) from segments (10,512) [2] 5,271 [3]  
Total assets 251,933 270,661  
Corporate assets      
Revenues:      
Net investment income 14,782 14,520  
Net realized investment gains 136 847  
Total assets 1,461,673 1,457,581  
Elimination      
Revenues:      
Gross written premiums 0 0  
Net written premiums 0 0  
Net earned premiums 0    
Commission and service fee income (14,049) [1] 0  
Policy and installment fee income 0 0  
Total segment revenues (14,049) 0  
Net losses and loss adjustment expenses (333) [2] 0 [3]  
Net commission expenses (10,571) [2] 0 [3]  
Other underwriting expenses (3,145) [2],[4] 0 [3],[5]  
Income (loss) from segments 0 [2] 0 [3]  
Total assets (29,871) 0  
Agency and Insurance Services | Segment assets      
Revenues:      
Gross written premiums 0 0  
Net written premiums 0 0  
Net earned premiums 0 0  
Commission and service fee income 14,049 [1] 0  
Policy and installment fee income 387 0  
Total segment revenues 14,436 0  
Net losses and loss adjustment expenses 0 [2] 0 [3]  
Net commission expenses 0 [2] 0 [3]  
Other underwriting expenses 12,632 [2],[4] 0 [3],[5]  
Income (loss) from segments 1,804 [2] 0 [3]  
Total assets 41,886 0  
Belmont Core | Segment assets      
Revenues:      
Gross written premiums 98,389 94,048  
Net written premiums 95,634 92,596  
Net earned premiums 92,260 89,132  
Commission and service fee income 0 [1] 0  
Policy and installment fee income 0 339  
Total segment revenues 92,260 89,471  
Net losses and loss adjustment expenses 66,452 [2] 48,909 [3]  
Net commission expenses 32,404 [2] 20,891 [3]  
Other underwriting expenses 4,986 [2],[4] 14,036 [3],[5]  
Income (loss) from segments (11,582) [2] 5,635 [3]  
Total assets 153,788 154,078  
Belmont Non-Core | Segment assets      
Revenues:      
Gross written premiums 286 (560)  
Net written premiums 230 (511)  
Net earned premiums 1,056 7,447  
Commission and service fee income 0 [1] 0  
Policy and installment fee income 30 6  
Total segment revenues 1,086 7,453  
Net losses and loss adjustment expenses 619 [2] 4,475 [3]  
Net commission expenses 501 [2] 2,532 [3]  
Other underwriting expenses 700 [2],[4] 810 [3],[5]  
Income (loss) from segments (734) [2] (364) [3]  
Total assets $ 86,130 $ 116,583  
[1] Consists of intersegment revenues, which are eliminated in consolidation.
[2] The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM.
[3] The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM.
[4] Other underwriting expenses consist primarily of personnel expenses and general operating expenses related to underwriting activities.
[5] Other underwriting expenses consist primarily of personnel expenses and general operating expenses related to underwriting activities.