Unpaid Losses and Settlement Expenses (Tables)	12 Months Ended
	Dec. 31, 2021
Unpaid Losses and Settlement Expenses [Abstract]
Summary of Cumulative Paid Losses and Settlement Expenses	PROPERTY LINESIncurred loss and settlement expenses, net of reinsurance (in thousands) As of December 31, 2021 Year Ended December 31, Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR plus expected development on reported claims Cumulative number of reported claims2012$ 6,143 $ 6,374 $ 6,406 $ 6,546 $ 6,482 $ 6,411 $ 6,455 $ 6,167 $ 6,161 $ 6,161  $ — 668 2013 9,266  8,302  8,290  8,415  8,471  8,282  8,272  8,270  8,275  11  626 2014 8,865  7,586  7,798  7,883  7,817  7,785  7,784  7,792  - 740 2015 7,693  7,494  7,717  7,634  7,654  7,636  7,635  10  554 2016 8,941  7,981  8,372  8,381  8,404  8,327  146  576 2017 13,993  13,568  13,741  13,825  13,622  24  715 2018 11,454  11,114  10,966  11,030  32  725 2019 13,933  14,758  14,976  81  833 2020 13,997  15,056  258  933 2021 12,968  (9) 701 Total$ 105,842  Cumulative paid loss and settlement expenses, net of reinsurance (in thousands) Year Ended December 31,Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 20212012$ 4,949 $ 6,401 $ 6,369 $ 6,362 $ 6,326 $ 6,472 $ 6,469 $ 6,176 $ 6,176 $ 6,176 2013 6,856  8,079  8,200  8,238  8,265  8,272  8,271  8,270  8,271 2014 6,243  7,631  7,746  7,796  7,795  7,795  7,801  7,803 2015 5,057  7,040  7,474  7,645  7,660  7,657  7,645 2016 6,157  7,624  8,236  8,356  8,437  8,465 2017 10,055  13,482  13,610  13,595  13,363 2018 8,487  11,009  11,025  11,062 2019 11,621  14,161  14,855 2020 10,620  14,485 2021 11,220 Total 103,345 Unpaid losses and settlement expense - years 2012 through 2021 2,497 Unpaid losses and settlement expense - prior to 2012 (36)Unpaid loss and settlement expense, net of reinsurance$ 2,461  *Presented as unaudited required supplementary information.‎ WORKERS' COMPENSATION AND LIABILITY LINESIncurred loss and settlement expenses, net of reinsurance (in thousands) As of December 31, 2021 Year Ended December 31, Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR plus expected development on reported claims Cumulative number of reported claims2012$ 13,122 $ 11,338 $ 11,407 $ 11,638 $ 12,692 $ 12,845 $ 12,632 $ 12,836 $ 12,801 $ 12,910  $ 10  1,155 2013 12,584  13,559  13,169  12,960  13,696  13,858  14,076  14,081  14,144  11  1,145 2014 13,385  14,744  15,341  16,718  16,881  16,996  16,953  16,929  98  1,213 2015 16,596  13,876  13,440  13,862  14,486  14,714  15,182  85  1,094 2016 16,677  14,843  16,240  16,855  17,547  18,413  (9) 1,041 2017 15,808  15,803  15,842  15,977  17,067  558  1,039 2018 18,308  17,122  17,082  16,925  1,553  1,126 2019 19,630  19,200  19,575  3,292  1,089 2020 17,359  14,106  3,925  615 2021 21,000  10,905  689 Total$ 166,251  Cumulative paid loss and settlement expenses, net of reinsurance (in thousands) Year Ended December 31,Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 20212012$ 1,180 $ 3,021 $ 5,589 $ 8,327 $ 10,913 $ 11,753 $ 12,156 $ 12,572 $ 12,698 $ 12,887 2013 1,579  4,156  7,634  10,423  12,181  12,980  13,565  13,741  13,974 2014 1,539  4,087  9,515  13,602  15,232  15,912  16,374  16,401 2015 1,408  4,319  7,404  10,528  12,487  13,262  13,932 2016 1,497  5,488  8,189  12,205  14,206  16,649 2017 1,523  5,419  8,753  11,878  14,771 2018 1,964  5,656  9,312  12,419 2019 3,664  7,453  12,132 2020 2,435  4,882 2021 3,520 Total 121,567 Unpaid losses and settlement expense - years 2012 through 2021 44,685 Unpaid losses and settlement expense - prior to 2012 168 Unpaid loss and settlement expense, net of reinsurance$ 44,853  *Presented as unaudited required supplementary information.‎ TOTAL LINESIncurred loss and settlement expenses, net of reinsurance (in thousands) As of December 31, 2021 Year Ended December 31, Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR plus expected development on reported claims Cumulative number of reported claims2012$ 19,265 $ 17,712 $ 17,813 $ 18,184 $ 19,174 $ 19,256 $ 19,087 $ 19,003 $ 18,962 $ 19,071  $ 10  1,823 2013 21,850  21,861  21,459  21,375  22,167  22,140  22,348  22,351  22,419  22  1,771 2014 22,250  22,330  23,139  24,601  24,698  24,781  24,737  24,721  98  1,953 2015 24,289  21,370  21,157  21,496  22,140  22,350  22,817  95  1,648 2016 25,618  22,824  24,612  25,236  25,951  26,740  137  1,617 2017 29,801  29,371  29,583  29,802  30,689  582  1,754 2018 29,762  28,236  28,048  27,955  1,585  1,851 2019 33,563  33,958  34,551  3,373  1,922 2020 31,356  29,162  4,183  1,548 2021 33,968  10,896  1,390 Total$ 272,093  Cumulative paid loss and settlement expenses, net of reinsurance (in thousands) Year Ended December 31,Accident Year 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 20212012$ 6,129 $ 9,422 $ 11,958 $ 14,689 $ 17,239 $ 18,225 $ 18,625 $ 18,748 $ 18,874 $ 19,063 2013 8,435  12,235  15,834  18,661  20,446  21,252  21,836  22,011  22,245 2014 7,782  11,718  17,261  21,398  23,027  23,707  24,175  24,204 2015 6,465  11,359  14,878  18,173  20,147  20,919  21,577 2016 7,654  13,112  16,425  20,561  22,643  25,114 2017 11,578  18,901  22,363  25,473  28,134 2018 10,451  16,665  20,337  23,481 2019 15,285  21,614  26,987 2020 13,055  19,367 2021 14,740 Total 224,912 Unpaid losses and settlement expense - years 2012 through 2021 47,182 Unpaid losses and settlement expense - prior to 2012 132 Unpaid loss and settlement expense, net of reinsurance$ 47,314  *Presented as unaudited required supplementary information.
Reconciliation of Loss Development	(In thousands) December 31, 2021Net unpaid losses and settlement expense Property Lines $ 2,461Workers' Compensation and Liability Lines 44,853Total unpaid losses and settlement expense, net of reinsurance 47,314Reinsurance recoverable on losses and settlement expense Property Lines 4,313Workers' Compensation and Liability Lines 10,208Total reinsurance recoverable on unpaid losses and settlement expense 14,521Total gross unpaid losses and LAE $ 61,835
Summary of Annual Percentage Payout	Average annual percentage payout of incurred losses by age, net of reinsurance Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9+Property Lines 75.1% 22.5% 1.4% 0.0% 0.0% 1.7% -0.4% 0.0% -0.1%Liability Lines 12.0% 20.6% 23.1% 19.9% 10.8% 5.4% 3.4% 2.2% 2.5%Total Lines 36.6% 21.8% 13.9% 12.0% 6.5% 3.9% 2.1% 1.5% 1.7%
Reconciliation of Unpaid Losses and Settlement Expenses	(In thousands) 2021 2020Unpaid losses and settlement expense - beginning of the period: Gross $ 61,576 $ 56,838Less: Ceded 13,020 11,036Net 48,556 45,802Increase in incurred losses and settlement expense: Current year 33,968 31,356Prior years 732 1,206Total incurred 34,700 32,562Deduct: Loss and settlement expense payments for claims incurred: Current year 14,740 13,054Prior years 21,203 16,754Total paid 35,943 29,808Net unpaid losses and settlement expense - end of the period 47,314 48,556Plus: Reinsurance recoverable on unpaid losses 14,521 13,020Gross unpaid losses and settlement expense - end of the period $ 61,835 $ 61,576