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v3.20.4

Schedule III - Supplementary Insurance Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deferred policy acquisition costs |  | $ 288,578 |  |  |  | $ 271,186 |  |  |  | $ 288,578 |  | $ 271,186 |  | $ 252,612 |
Reserve for loss and loss expenses |  | 4,260,355 |  |  |  | 4,067,163 |  |  |  | 4,260,355 |  | 4,067,163 |  | 3,893,868 |
Unearned premiums |  | 1,618,271 |  |  |  | 1,523,167 |  |  |  | 1,618,271 |  | 1,523,167 |  | 1,431,932 |
Net premiums earned |  |  |  |  |  |  |  |  |  | 2,681,814 |  | 2,597,171 |  | 2,436,229 |
Net investment income | [1] |  |  |  |  |  |  |  |  | 222,890 |  | 236,965 |  | 140,413 |
Loss and loss expense incurred |  |  |  |  |  |  |  |  |  | 1,635,823 |  | 1,551,491 |  | 1,498,134 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  | 560,271 |  | 535,973 |  | 495,042 |
Other operating expenses |  |  |  |  |  |  |  |  |  | 349,371 | [2] | 345,714 | [3] | 321,880 | [4]
Net premiums written |  |  |  |  |  |  |  |  |  | 2,773,092 |  | 2,679,424 |  | 2,514,286 |
Other insurance expenses |  |  |  |  |  |  |  |  |  | 366,941 |  | 358,069 |  | 331,318 |
Other income |  | 4,943 | $ 6,119 | $ 4,683 | $ 1,825 | 3,820 | $ 3,162 | $ 3,053 | $ 2,320 | 17,570 |  | 12,355 |  | 9,438 |
Standard Commercial Lines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred policy acquisition costs |  | 246,494 |  |  |  | 226,464 |  |  |  | 246,494 |  | 226,464 |  | 206,391 |
Reserve for loss and loss expenses |  | 3,596,340 |  |  |  | 3,436,363 |  |  |  | 3,596,340 |  | 3,436,363 |  | 3,283,531 |
Unearned premiums |  | 1,196,243 |  |  |  | 1,108,009 |  |  |  | 1,196,243 |  | 1,108,009 |  | 1,020,054 |
Net premiums earned |  |  |  |  |  |  |  |  |  | 2,143,184 |  | 2,049,614 |  | 1,912,222 |
Net investment income |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Loss and loss expense incurred |  |  |  |  |  |  |  |  |  | 1,245,627 |  | 1,187,856 |  | 1,141,038 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  | 474,322 |  | 445,661 |  | 412,420 |
Other operating expenses |  |  |  |  |  |  |  |  |  | 271,504 |  | 270,107 |  | 249,660 |
Net premiums written |  |  |  |  |  |  |  |  |  | 2,230,636 |  | 2,137,071 |  | 1,975,683 |
Other income |  |  |  |  |  |  |  |  |  | 15,512 |  | 10,889 |  | 8,180 |
E&S Lines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred policy acquisition costs |  | 28,281 |  |  |  | 27,874 |  |  |  | 28,281 |  | 27,874 |  | 28,151 |
Reserve for loss and loss expenses |  | 435,667 |  |  |  | 406,600 |  |  |  | 435,667 |  | 406,600 |  | 387,114 |
Unearned premiums |  | 113,845 |  |  |  | 106,033 |  |  |  | 113,845 |  | 106,033 |  | 107,793 |
Net premiums earned |  |  |  |  |  |  |  |  |  | 239,490 |  | 239,818 |  | 219,566 |
Net investment income |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Loss and loss expense incurred |  |  |  |  |  |  |  |  |  | 156,936 |  | 152,335 |  | 150,344 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  | 55,255 |  | 55,835 |  | 49,005 |
Other operating expenses |  |  |  |  |  |  |  |  |  | 27,173 |  | 21,905 |  | 20,912 |
Net premiums written |  |  |  |  |  |  |  |  |  | 247,290 |  | 237,761 |  | 229,326 |
Other income |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 1 |
Miscellaneous Income [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other income |  |  |  |  |  |  |  |  |  | 17,570 |  | 12,355 |  | 9,438 |
Standard Personal Lines |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred policy acquisition costs |  | 13,803 |  |  |  | 16,848 |  |  |  | 13,803 |  | 16,848 |  | 18,070 |
Reserve for loss and loss expenses |  | 228,348 |  |  |  | 224,200 |  |  |  | 228,348 |  | 224,200 |  | 223,223 |
Unearned premiums |  | 308,183 |  |  |  | 309,125 |  |  |  | 308,183 |  | 309,125 |  | 304,085 |
Net premiums earned |  |  |  |  |  |  |  |  |  | 299,140 |  | 307,739 |  | 304,441 |
Net investment income |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Loss and loss expense incurred |  |  |  |  |  |  |  |  |  | 233,260 |  | 211,300 |  | 206,752 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  | 30,694 |  | 34,477 |  | 33,617 |
Other operating expenses |  |  |  |  |  |  |  |  |  | 50,694 |  | 53,702 |  | 51,308 |
Net premiums written |  |  |  |  |  |  |  |  |  | 295,166 |  | 304,592 |  | 309,277 |
Other income |  |  |  |  |  |  |  |  |  | 2,058 |  | 1,466 |  | 1,257 |
Investments SIGI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred policy acquisition costs |  | 0 |  |  |  | 0 |  |  |  | 0 |  | 0 |  | 0 |
Reserve for loss and loss expenses |  | 0 |  |  |  | 0 |  |  |  | 0 |  | 0 |  | 0 |
Unearned premiums |  | $ 0 |  |  |  | $ 0 |  |  |  | 0 |  | 0 |  | 0 |
Net premiums earned |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Net investment income | [1] |  |  |  |  |  |  |  |  | 222,890 |  | 236,965 |  | 140,413 |
Loss and loss expense incurred |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Amortization of deferred policy acquisition costs |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Other operating expenses |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Net premiums written |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 0 |  | $ 0 |
[1] | Includes “Net investment income earned” and “Net realized and unrealized investment (losses) gains” on the Consolidated Statements of Income.
[2] | “Other operating expenses” of $349,371 reconciles to the Consolidated Statements of Income
[3] | “Other operating expenses” of $345,714 reconciles to the Consolidated Statements of Income
[4] | “Other operating expenses” of $321,880 reconciles to the Consolidated Statements of Income

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