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Reserve for Loss and Loss Expense (Claims Development) (Details) $ in Thousands | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | $ 15,332,846 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 11,128,130 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 4,566,037 |  |  |  |  |  |  |  |  |
Reserve for loss and loss expense | 5,336,911 | $ 5,144,821 |  |  |  |  |  |  |  |
Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 361,321 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014[Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,087,700 | 1,090,345 | $ 1,094,367 | $ 1,089,529 | $ 1,100,208 | $ 1,104,218 | $ 1,124,014 | $ 1,146,990 | $ 1,133,798 | $ 1,107,513
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 33,872 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 95,785 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,040,893 | 1,032,400 | 1,020,961 | 1,002,157 | 981,868 | 936,425 | 855,959 | 736,154 | 614,075 | 405,898
Short-duration Insurance Contracts, Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,105,039 | 1,103,543 | 1,103,592 | 1,108,860 | 1,119,441 | 1,138,313 | 1,144,830 | 1,130,513 | 1,114,081 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 38,133 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 95,468 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,032,064 | 1,018,023 | 1,000,509 | 967,857 | 929,222 | 845,868 | 725,385 | 581,203 | 376,641 |
Short-duration Insurance Contracts, Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,163,467 | 1,167,539 | 1,171,273 | 1,180,829 | 1,199,734 | 1,227,142 | 1,203,634 | 1,188,608 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 47,702 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 96,324 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,088,453 | 1,061,952 | 1,025,264 | 983,852 | 892,390 | 764,331 | 617,958 | 387,272 |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,287,882 | 1,273,039 | 1,268,941 | 1,288,526 | 1,313,585 | 1,313,372 | 1,270,110 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 63,595 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 100,292 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,180,346 | 1,116,336 | 1,050,258 | 954,792 | 829,134 | 678,453 | 433,440 |  |  |
Short-duration Insurance Contract, Accident Year 2018 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,424,953 | 1,425,540 | 1,441,303 | 1,457,415 | 1,461,603 | 1,413,800 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 98,900 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 107,541 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,252,623 | 1,187,744 | 1,083,556 | 942,893 | 779,466 | 511,271 |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,523,313 | 1,529,859 | 1,526,566 | 1,523,041 | 1,483,945 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 169,855 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 104,668 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,247,100 | 1,109,628 | 949,996 | 781,462 | 510,091 |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,531,446 | 1,550,195 | 1,587,607 | 1,591,972 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 243,526 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 95,537 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,152,227 | 988,463 | 831,976 | 572,302 |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,774,984 | 1,781,054 | 1,784,661 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 438,488 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 99,553 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,134,930 | 934,965 | 609,889 |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 2,096,742 | 2,073,343 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 690,322 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 105,549 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,155,527 | 699,789 |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 2,337,320 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,169,504 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 101,414 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 843,967 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 3,468,736 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 1,712,824 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 1,874,944 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,671,146 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 1,112,122 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 767,784 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 3,956,413 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 3,021,770 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 939,644 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 640,270 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 547,925 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 101,601 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 2,008,483 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 1,875,394 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 133,412 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 119,032 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 208,760 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 5,001 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 9,256 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 323 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 226,407 | 228,933 | 230,247 | 229,679 | 237,125 | 234,082 | 239,333 | 257,132 | 249,946 | 244,312
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 13,296 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,725 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 208,521 | 204,212 | 198,772 | 187,352 | 179,192 | 154,957 | 121,969 | 79,972 | 46,825 | 14,901
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 156,750 | 158,479 | 161,021 | 159,604 | 160,646 | 164,420 | 172,515 | 182,579 | 187,065 | 199,346
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 15,581 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,495 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 134,338 | 132,809 | 130,726 | 127,858 | 124,077 | 119,392 | 113,626 | 100,876 | 78,944 | 35,924
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 215,073 | 214,816 | 214,992 | 216,461 | 217,334 | 218,172 | 219,925 | 216,824 | 212,725 | 200,534
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 276 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 28,447 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 214,564 | 213,847 | 213,689 | 212,481 | 209,655 | 202,821 | 180,701 | 148,884 | 117,169 | 80,810
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 57,649 | 57,355 | 57,483 | 57,302 | 58,093 | 58,517 | 59,806 | 62,548 | 60,949 | 55,962
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (21) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 4,067 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 57,670 | 56,861 | 55,729 | 55,708 | 55,458 | 52,940 | 49,460 | 44,911 | 40,584 | 28,914
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 136,370 | 136,112 | 136,151 | 136,237 | 136,212 | 138,155 | 138,751 | 136,820 | 136,249 | 141,192
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,517 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 136,362 | 136,107 | 136,141 | 135,928 | 136,008 | 137,418 | 137,883 | 136,634 | 132,909 | 101,131
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 213,653 | 210,137 | 211,768 | 214,176 | 219,204 | 233,249 | 246,990 | 245,710 | 254,720 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16,595 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,596 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 186,336 | 179,117 | 173,697 | 157,071 | 144,216 | 116,804 | 78,668 | 39,978 | 14,665 |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 166,042 | 169,008 | 170,577 | 172,572 | 176,242 | 179,642 | 183,604 | 194,639 | 193,729 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 15,698 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,554 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 133,272 | 132,235 | 129,019 | 124,046 | 120,097 | 112,601 | 98,195 | 77,320 | 33,857 |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 263,115 | 262,766 | 262,054 | 261,386 | 260,565 | 259,495 | 253,074 | 240,958 | 220,994 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 470 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 30,332 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 260,328 | 257,668 | 255,600 | 249,905 | 238,142 | 211,515 | 175,866 | 132,260 | 91,347 |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 51,457 | 52,514 | 52,200 | 52,325 | 54,454 | 55,925 | 57,245 | 53,768 | 52,871 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 24 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,971 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 51,308 | 51,120 | 50,005 | 49,839 | 49,073 | 46,571 | 42,710 | 36,014 | 24,189 |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 112,974 | 112,915 | 112,937 | 112,582 | 112,496 | 111,566 | 111,750 | 109,513 | 110,270 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,407 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 112,568 | 112,391 | 112,410 | 112,117 | 110,969 | 110,994 | 109,829 | 106,182 | 79,048 |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 244,782 | 243,669 | 246,643 | 252,733 | 263,245 | 277,986 | 272,048 | 277,214 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 22,161 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,900 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 211,725 | 199,032 | 181,770 | 164,136 | 133,757 | 89,431 | 46,549 | 15,684 |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 147,732 | 151,961 | 155,210 | 156,540 | 166,009 | 176,248 | 184,946 | 196,774 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 17,164 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,587 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 123,232 | 122,186 | 119,800 | 115,159 | 109,166 | 98,037 | 78,531 | 34,525 |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 294,878 | 294,297 | 291,674 | 290,359 | 285,304 | 285,302 | 274,367 | 255,187 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,457 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 32,324 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 288,512 | 284,870 | 277,242 | 264,858 | 233,939 | 200,701 | 155,720 | 106,022 |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 52,930 | 53,201 | 53,147 | 53,367 | 53,835 | 54,993 | 53,792 | 52,335 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 280 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,857 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 52,427 | 52,070 | 50,536 | 48,786 | 45,308 | 39,973 | 36,848 | 24,655 |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 123,067 | 123,126 | 123,005 | 123,567 | 124,487 | 125,937 | 126,185 | 121,927 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,743 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 123,203 | 123,265 | 122,909 | 123,601 | 123,828 | 122,930 | 118,789 | 83,966 |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 293,448 | 283,379 | 278,607 | 289,883 | 301,384 | 293,128 | 293,747 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 33,861 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 11,426 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 241,879 | 201,948 | 167,002 | 131,980 | 92,355 | 49,470 | 17,366 |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 148,949 | 151,221 | 154,159 | 162,672 | 175,853 | 184,306 | 195,202 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16,019 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,814 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 123,573 | 120,468 | 116,426 | 110,645 | 100,645 | 82,216 | 40,375 |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 326,832 | 325,654 | 326,461 | 322,197 | 324,291 | 329,389 | 301,274 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2,984 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 33,627 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 318,047 | 309,810 | 296,600 | 262,349 | 220,422 | 178,823 | 117,287 |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 42,408 | 42,374 | 43,606 | 48,067 | 51,524 | 48,698 | 46,624 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 416 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,897 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 41,217 | 40,845 | 39,940 | 40,359 | 36,950 | 31,337 | 21,865 |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 155,408 | 154,942 | 154,119 | 153,664 | 149,044 | 149,106 | 138,773 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 22 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,907 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 155,236 | 154,689 | 153,750 | 152,018 | 148,589 | 142,338 | 99,047 |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 329,102 | 324,567 | 332,013 | 345,224 | 336,326 | 317,934 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 57,847 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 11,924 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 236,812 | 197,286 | 155,538 | 108,421 | 60,784 | 19,531 |  |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 163,884 | 167,974 | 173,428 | 181,151 | 193,818 | 193,894 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 20,739 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 11,136 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 129,869 | 126,206 | 119,904 | 105,903 | 84,780 | 41,122 |  |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 346,213 | 348,202 | 350,310 | 345,547 | 352,487 | 347,908 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 5,190 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 36,286 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 330,584 | 319,819 | 291,725 | 243,713 | 193,788 | 134,867 |  |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 55,586 | 56,625 | 60,393 | 62,427 | 57,202 | 55,024 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,169 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 4,264 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 52,496 | 51,239 | 48,144 | 44,316 | 39,791 | 29,995 |  |  |  |
Standard Commercial Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 196,527 | 196,413 | 194,016 | 192,558 | 190,834 | 183,177 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 40 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,294 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 196,605 | 196,376 | 193,487 | 192,698 | 184,813 | 135,416 |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 362,139 | 366,184 | 358,301 | 356,363 | 347,150 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 98,841 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 11,767 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 213,020 | 160,680 | 100,206 | 58,284 | 18,097 |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 159,225 | 164,940 | 174,912 | 188,596 | 188,625 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 22,629 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,330 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 119,875 | 112,649 | 100,812 | 77,878 | 37,826 |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 410,432 | 407,051 | 404,854 | 398,346 | 385,212 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16,701 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 36,653 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 376,550 | 331,152 | 283,410 | 221,590 | 149,538 |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 64,721 | 65,762 | 64,667 | 59,466 | 53,531 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3,129 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,650 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 60,076 | 52,887 | 46,113 | 41,587 | 27,718 |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 180,832 | 180,605 | 179,574 | 177,075 | 173,826 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 88 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,315 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 180,179 | 179,538 | 177,825 | 172,768 | 130,891 |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 361,163 | 352,834 | 360,302 | 361,554 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 142,886 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,050 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 159,209 | 100,356 | 58,699 | 21,858 |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 143,384 | 159,229 | 168,594 | 168,643 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 21,785 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,551 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 102,142 | 87,211 | 68,277 | 29,559 |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 374,293 | 375,636 | 381,163 | 381,654 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 37,371 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 30,533 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 306,355 | 254,365 | 198,034 | 139,016 |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 73,320 | 73,077 | 73,680 | 71,836 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2,777 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 5,443 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 66,478 | 60,596 | 57,210 | 43,376 |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 226,915 | 226,107 | 225,278 | 232,060 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,345 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,155 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 223,902 | 220,953 | 215,107 | 164,613 |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 414,204 | 414,279 | 422,748 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 209,078 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 10,916 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 131,157 | 71,664 | 28,069 |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 173,784 | 185,151 | 185,198 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 52,182 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,580 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 96,674 | 76,015 | 32,918 |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 510,825 | 512,673 | 483,831 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 92,709 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 37,184 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 352,383 | 283,411 | 187,200 |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 72,231 | 63,648 | 66,312 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 11,352 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,520 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 54,651 | 47,436 | 34,412 |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 237,831 | 239,822 | 246,319 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 859 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,983 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 235,217 | 227,259 | 161,757 |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 482,279 | 482,590 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 308,245 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 11,275 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 93,422 | 31,502 |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 207,156 | 207,206 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 70,491 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,963 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 99,894 | 45,814 |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 581,223 | 572,421 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 170,627 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 39,879 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 336,516 | 216,180 |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 89,025 | 86,194 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16,496 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,750 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 66,581 | 36,421 |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 296,974 | 297,318 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 4,467 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,828 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 285,250 | 186,677 |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | General Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 541,559 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 453,175 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 9,213 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 30,743 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | Workers Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 204,240 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 106,226 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,331 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 49,253 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | Commercial Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 633,529 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 308,059 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 36,860 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 237,931 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | Business Owners' Policies [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 80,943 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 23,721 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,129 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 45,021 |  |  |  |  |  |  |  |  |
Standard Commercial Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | Commercial Property [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 341,585 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 53,704 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,129 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 226,872 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,144,541 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 1,025,143 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 125,940 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 863,067 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 809,870 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 58,334 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 6,542 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 5,137 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2014[Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 107,390 | 107,543 | 107,566 | 107,106 | 107,104 | 106,821 | 107,452 | 106,757 | 109,325 | 102,250
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 22,510 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 107,381 | 107,325 | 107,108 | 106,478 | 105,709 | 104,055 | 99,173 | 92,589 | 83,739 | 62,519
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2014[Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 83,796 | 83,819 | 83,830 | 83,525 | 83,824 | 83,539 | 83,844 | 83,637 | 82,461 | 80,111
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 37 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 8,776 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 83,782 | 83,782 | 83,321 | 82,831 | 82,836 | 82,583 | 81,664 | 79,751 | 76,007 | 61,561
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 98,939 | 98,669 | 98,596 | 98,588 | 98,718 | 99,570 | 100,214 | 99,698 | 96,387 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 53 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 20,866 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 98,483 | 97,920 | 97,761 | 97,275 | 95,997 | 92,102 | 87,163 | 76,470 | 58,725 |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 74,265 | 74,237 | 74,682 | 74,673 | 74,978 | 74,723 | 76,559 | 76,400 | 76,637 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 44 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,754 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 74,108 | 74,108 | 74,096 | 74,052 | 74,079 | 72,927 | 72,202 | 70,078 | 52,589 |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 100,458 | 100,395 | 99,858 | 99,544 | 101,140 | 100,202 | 98,032 | 92,727 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 113 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 19,827 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 100,315 | 99,656 | 98,977 | 98,080 | 94,372 | 86,752 | 76,823 | 57,961 |  |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 60,453 | 60,841 | 60,855 | 61,735 | 61,723 | 62,391 | 60,931 | 60,105 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 45 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,896 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 60,480 | 60,474 | 60,449 | 61,187 | 60,082 | 59,546 | 57,333 | 42,252 |  |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 105,243 | 105,079 | 103,557 | 103,260 | 103,653 | 105,139 | 101,880 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 435 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 20,751 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 104,114 | 103,556 | 100,521 | 97,628 | 91,479 | 82,730 | 62,854 |  |  |
Standard Personal Lines | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 68,919 | 68,902 | 68,938 | 70,064 | 70,365 | 67,978 | 59,167 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 463 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,391 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 68,454 | 68,282 | 68,078 | 67,767 | 67,193 | 63,290 | 45,466 |  |  |
Standard Personal Lines | Short-duration Insurance Contract, Accident Year 2018 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 113,037 | 113,647 | 112,418 | 112,030 | 113,569 | 111,594 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 781 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 22,685 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 110,894 | 109,644 | 107,026 | 99,982 | 89,628 | 69,721 |  |  |  |
Standard Personal Lines | Short-duration Insurance Contract, Accident Year 2018 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 68,581 | 68,416 | 68,931 | 69,832 | 68,526 | 62,961 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 757 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,609 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 67,726 | 67,739 | 66,634 | 65,348 | 64,137 | 49,430 |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 119,632 | 118,669 | 115,993 | 115,688 | 114,043 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,871 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 22,872 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 115,919 | 109,844 | 102,930 | 92,162 | 69,699 |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 72,856 | 73,070 | 73,816 | 72,772 | 64,306 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,061 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,010 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 71,603 | 70,880 | 69,911 | 67,631 | 49,680 |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2020 | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 89,027 | 90,179 | 94,532 | 95,625 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2,537 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 17,548 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 83,137 | 76,710 | 68,691 | 53,407 |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2020 | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 112,590 | 113,804 | 112,523 | 109,033 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1,345 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 9,835 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 110,578 | 109,145 | 105,690 | 83,838 |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2021 | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 105,088 | 102,777 | 108,244 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 5,963 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 19,730 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 94,480 | 84,743 | 65,325 |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2021 | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 84,189 | 83,295 | 82,425 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3,612 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,919 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 79,399 | 77,018 | 59,054 |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2022 | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 133,623 | 121,030 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 16,991 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 21,262 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 107,778 | 75,994 |  |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2022 | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 100,389 | 93,826 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 5,017 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 6,869 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 91,788 | 68,832 |  |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2023 | Personal Automobile [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 172,104 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 45,030 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 25,893 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 102,642 |  |  |  |  |  |  |  |  |
Standard Personal Lines | Short-Duration Insurance Contract, Accident Year 2023 | Homeowners [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 137,029 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 24,058 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 7,051 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 101,952 |  |  |  |  |  |  |  |  |
E&S Lines [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 1,110,366 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 598,439 |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 517,988 |  |  |  |  |  |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contracts, Accident Years Prior to 2014 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense, Net | 6,061 |  |  |  |  |  |  |  |  |
E&S Lines [Member] | Short-duration Insurance Contracts, Accident Year 2014[Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 75,436 | 74,538 | 74,270 | 70,846 | 71,153 | 71,206 | 71,719 | 69,929 | 63,505 | 55,316
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 4,631 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 1,888,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 69,498 | 68,648 | 66,661 | 64,698 | 60,092 | 53,780 | 43,877 | 25,571 | 12,234 | $ 2,353
E&S Lines [Member] | Short-duration Insurance Contracts, Accident Year 2015 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 91,424 | 90,263 | 87,662 | 90,126 | 90,355 | 90,488 | 82,404 | 76,432 | 75,498 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 5,159 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 2,899,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 83,587 | 81,396 | 75,844 | 71,421 | 64,529 | 50,712 | 29,389 | 13,057 | $ 3,036 |
E&S Lines [Member] | Short-duration Insurance Contracts, Accident Year 2016 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 101,105 | 101,873 | 102,476 | 104,730 | 105,120 | 104,655 | 96,416 | 94,451 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 6,299 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 3,015,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 90,665 | 81,932 | 75,004 | 69,448 | 56,581 | 33,950 | 16,195 | $ 3,720 |  |
E&S Lines [Member] | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 106,663 | 102,045 | 99,960 | 99,395 | 99,866 | 95,783 | 91,438 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 9,143 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 2,866,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 88,294 | 77,090 | 68,266 | 53,238 | 34,179 | 14,672 | $ 5,057 |  |  |
E&S Lines [Member] | Short-duration Insurance Contract, Accident Year 2018 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 106,490 | 105,756 | 104,983 | 103,184 | 103,004 | 98,324 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 12,001 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 2,843,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 82,549 | 73,605 | 57,962 | 39,174 | 21,337 | $ 5,509 |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contract, Accident Year 2019 [Member] | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 114,802 | 117,113 | 117,736 | 118,298 | 117,087 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 23,476 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 2,752,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 73,779 | 57,701 | 35,844 | 17,812 | $ 4,422 |  |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contract, Accident Year 2020 | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 91,077 | 95,832 | 103,137 | 103,872 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 30,090 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 1,891,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 46,349 | 27,861 | 13,064 | $ 3,695 |  |  |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contract, Accident Year 2021 | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 120,191 | 125,436 | 128,099 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 60,356 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 1,991,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 37,213 | 15,835 | $ 4,326 |  |  |  |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contract, Accident Year 2022 | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 145,918 | 146,999 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 96,255 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 1,944,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 21,618 | $ 4,198 |  |  |  |  |  |  |  |
E&S Lines [Member] | Short-Duration Insurance Contract, Accident Year 2023 | Casualty Insurance Product Line [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Net outstanding liabilities | 157,260 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 137,488 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | 1,242,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 4,887 |  |  |  |  |  |  |  |  |

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