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Short Duration Contracts - Claims development - Reinsurance (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | $ 23,906 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 5,210 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 1,831 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 406 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 3,785 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 289 | $ 287 | $ 285 | $ 277 | $ 273 | $ 274 | $ 267 | $ 252 | $ 228 | $ 216
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 197 | 188 | 174 | 158 | 133 | 114 | 87 | 52 | 26 | 6
Total of IBNR liabilities plus expected development on reported claims | 45 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 346 | 343 | 336 | 321 | 314 | 302 | 274 | 258 | 271 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 239 | 224 | 190 | 165 | 138 | 113 | 64 | 30 | 6 |
Total of IBNR liabilities plus expected development on reported claims | 55 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 332 | 328 | 314 | 304 | 291 | 286 | 295 | 281 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 224 | 207 | 183 | 155 | 129 | 107 | 31 | 8 |  |
Total of IBNR liabilities plus expected development on reported claims | 53 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 402 | 405 | 406 | 384 | 372 | 346 | 336 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 287 | 258 | 220 | 131 | 97 | 58 | 16 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 65 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 365 | 399 | 379 | 360 | 377 | 389 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 202 | 178 | 132 | 90 | 51 | 18 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 108 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 464 | 428 | 428 | 438 | 444 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 236 | 191 | 103 | 54 | 15 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 163 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 539 | 546 | 533 | 552 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 182 | 114 | 62 | 18 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 241 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 695 | 669 | 664 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 173 | 88 | 19 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 385 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 776 | 734 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 66 | 14 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 624 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2025 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,002 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 25 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 928 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,980 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 1,062 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 2 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 920 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 4 | 4 | 4 | 5 | 6 | 6 | 9 | 12 | 16 | 23
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 3 | 2 | 2 | 2 | 2 | 2 | 3 | 2 | 2 | (7)
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 20 | 21 | 21 | 21 | 24 | 36 | 50 | 54 | 86 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 17 | 17 | 17 | 16 | 14 | 27 | 37 | 32 | 31 |
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | (4) | (2) | 0 | 3 | 12 | 25 | 44 | 69 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (12) | (11) | (13) | (14) | (17) | 12 | 2 | 27 |  |
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | (8) | (7) | (11) | (4) | 4 | 4 | 12 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (26) | (25) | (16) | (17) | 8 | 4 | 4 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 1 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 321 | 319 | 330 | 341 | 337 | 272 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 271 | 262 | 251 | 208 | 158 | 57 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 5 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 302 | 307 | 305 | 318 | 323 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 243 | 239 | 230 | 177 | 66 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 11 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 262 | 273 | 298 | 306 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 219 | 211 | 169 | 70 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 30 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 227 | 272 | 272 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 120 | 84 | 8 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 18 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 441 | 512 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 145 | 60 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 67 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2025 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 415 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 82 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 84 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 5,150 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 3,055 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 8 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 2,103 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 124 | 127 | 130 | 129 | 135 | 138 | 135 | 136 | 144 | 174
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 116 | 117 | 114 | 114 | 113 | 111 | 103 | 98 | 94 | 33
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 197 | 201 | 202 | 205 | 213 | 230 | 237 | 250 | 267 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 186 | 186 | 186 | 182 | 178 | 164 | 155 | 124 | 28 |
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 197 | 203 | 203 | 202 | 212 | 235 | 239 | 223 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 181 | 177 | 177 | 175 | 167 | 151 | 107 | 30 |  |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 193 | 196 | 190 | 190 | 195 | 206 | 216 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 174 | 170 | 169 | 162 | 150 | 124 | 43 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 11 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 313 | 322 | 320 | 319 | 339 | 368 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 291 | 280 | 266 | 243 | 207 | 101 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | (1) |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 500 | 499 | 491 | 497 | 546 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 457 | 424 | 363 | 269 | 136 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 14 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 656 | 660 | 670 | 745 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 526 | 468 | 360 | 142 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 70 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 744 | 740 | 839 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 489 | 382 | 151 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 117 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,056 | 1,212 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 445 | 144 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 325 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2025 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,170 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 190 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 648 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,041 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 447 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 18 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 612 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 10 | 11 | 11 | 12 | 15 | 17 | 19 | 23 | 23 | 27
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 8 | 7 | 7 | 7 | 7 | 6 | 3 | 0 | (2) | (7)
Total of IBNR liabilities plus expected development on reported claims | 2 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 15 | 15 | 15 | 17 | 20 | 21 | 24 | 26 | 29 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 12 | 12 | 12 | 12 | 12 | 11 | 9 | 7 | 2 |
Total of IBNR liabilities plus expected development on reported claims | 2 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 19 | 20 | 21 | 21 | 24 | 24 | 25 | 27 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 16 | 16 | 15 | 14 | 13 | 11 | 7 | 2 |  |
Total of IBNR liabilities plus expected development on reported claims | 2 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 60 | 63 | 62 | 61 | 60 | 55 | 48 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 49 | 49 | 43 | 35 | 29 | 22 | 11 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 81 | 82 | 80 | 80 | 76 | 83 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 71 | 66 | 60 | 42 | 26 | 9 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 4 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 86 | 79 | 82 | 96 | 110 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 68 | 53 | 45 | 24 | 8 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 8 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 167 | 134 | 138 | 126 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 86 | 63 | 37 | 12 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 38 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 156 | 170 | 161 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 77 | 43 | 13 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 44 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 220 | 233 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 44 | 18 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 100 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2025 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 227 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 16 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 172 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 8,564 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 4,930 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 35 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 3,669 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 315 | 312 | 319 | 318 | 321 | 326 | 319 | 328 | 335 | 338
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 305 | 304 | 305 | 301 | 295 | 288 | 271 | 251 | 213 | $ 113
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 378 | 372 | 376 | 379 | 384 | 386 | 385 | 405 | 412 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 362 | 361 | 360 | 350 | 339 | 325 | 309 | 266 | $ 141 |
Total of IBNR liabilities plus expected development on reported claims | 11 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 425 | 431 | 438 | 438 | 442 | 417 | 423 | 431 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 392 | 393 | 389 | 366 | 348 | 326 | 286 | $ 135 |  |
Total of IBNR liabilities plus expected development on reported claims | 16 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 398 | 413 | 418 | 408 | 412 | 418 | 441 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 354 | 355 | 335 | 313 | 286 | 217 | $ 126 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 25 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 532 | 543 | 551 | 531 | 536 | 607 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 471 | 453 | 413 | 377 | 299 | $ 138 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 36 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 638 | 637 | 630 | 629 | 628 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 546 | 508 | 443 | 319 | $ 156 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 33 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 950 | 991 | 942 | 962 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 698 | 627 | 465 | $ 186 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 108 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,321 | 1,230 | 1,303 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 714 | 502 | $ 207 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 330 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,647 | 1,696 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 705 | $ 331 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 623 |  |  |  |  |  |  |  |  |
Reinsurance | Specialty | 2025 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,960 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 383 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | $ 1,275 |  |  |  |  |  |  |  |  |

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