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Short Duration Contracts - Claims development - Reinsurance (Details) - USD ($) $ in Millions | 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 | Dec. 31, 2015
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | $ 21,118 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 4,295 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 1,623 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 354 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 3,026 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 248 | $ 257 | $ 248 | $ 246 | $ 243 | $ 236 | $ 232 | $ 225 | $ 217 | $ 218
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 177 | 169 | 151 | 136 | 119 | 96 | 71 | 47 | 20 | 4
Total of IBNR liabilities plus expected development on reported claims | 37 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 279 | 278 | 269 | 266 | 266 | 259 | 244 | 222 | 209 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 186 | 172 | 156 | 132 | 113 | 86 | 51 | 26 | 6 |
Total of IBNR liabilities plus expected development on reported claims | 43 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 335 | 327 | 313 | 306 | 295 | 268 | 252 | 264 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 221 | 188 | 164 | 137 | 113 | 64 | 30 | 6 |  |
Total of IBNR liabilities plus expected development on reported claims | 49 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 318 | 304 | 295 | 283 | 278 | 286 | 273 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 205 | 182 | 154 | 129 | 106 | 31 | 8 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 49 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 398 | 399 | 378 | 367 | 340 | 328 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 256 | 219 | 130 | 97 | 58 | 16 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 72 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 385 | 366 | 348 | 365 | 377 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 177 | 131 | 90 | 50 | 18 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 128 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 423 | 422 | 431 | 436 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 190 | 102 | 53 | 14 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 157 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 535 | 523 | 542 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 111 | 60 | 17 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 312 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 654 | 650 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 86 | 18 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 438 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 720 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 14 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 680 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,601 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 791 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 2 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 812 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 2 | 2 | 2 | 2 | 3 | 3 | 5 | 11 | 17 | 32
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 2 | 1 | 1 | 1 | 1 | 1 | 2 | 1 | (3) | (3)
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 3 | 3 | 4 | 5 | 5 | 8 | 11 | 15 | 21 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 2 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | (7) |
Total of IBNR liabilities plus expected development on reported claims | 1 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 20 | 20 | 20 | 23 | 35 | 48 | 53 | 85 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 16 | 16 | 15 | 13 | 26 | 36 | 31 | 31 |  |
Total of IBNR liabilities plus expected development on reported claims | (1) |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | (2) | (1) | 2 | 11 | 25 | 43 | 68 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (12) | (14) | (15) | (18) | 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 | (10) | (14) | (7) | 1 | 2 | 10 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (27) | (19) | (19) | 6 | 3 | 4 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 308 | 320 | 329 | 325 | 262 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 253 | 243 | 203 | 155 | 55 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 9 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 288 | 286 | 301 | 307 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 224 | 217 | 168 | 66 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 7 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 258 | 284 | 292 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 200 | 162 | 68 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 25 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 245 | 253 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 75 | 6 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 34 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 489 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 58 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 100 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 4,241 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 2,470 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 6 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 1,777 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 166 | 166 | 166 | 171 | 175 | 186 | 187 | 183 | 187 | 213
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 159 | 159 | 158 | 158 | 157 | 164 | 159 | 148 | 118 | 75
Total of IBNR liabilities plus expected development on reported claims | 4 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 126 | 128 | 127 | 133 | 137 | 133 | 135 | 143 | 172 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 115 | 113 | 113 | 112 | 110 | 102 | 97 | 93 | 33 |
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 197 | 198 | 201 | 209 | 225 | 233 | 244 | 263 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 182 | 182 | 178 | 175 | 160 | 153 | 123 | 27 |  |
Total of IBNR liabilities plus expected development on reported claims | 7 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 201 | 201 | 199 | 209 | 232 | 236 | 221 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 175 | 175 | 173 | 165 | 150 | 106 | 29 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 193 | 187 | 187 | 192 | 202 | 212 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 167 | 166 | 160 | 148 | 122 | 42 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 4 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 319 | 317 | 316 | 336 | 363 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 277 | 264 | 241 | 206 | 100 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 14 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 491 | 483 | 489 | 537 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 418 | 358 | 265 | 135 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 28 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 645 | 654 | 728 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 459 | 354 | 141 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 74 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 720 | 819 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 375 | 149 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 136 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,183 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 143 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 687 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 824 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 347 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 18 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 495 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 24 | 24 | 25 | 27 | 28 | 30 | 31 | 31 | 37 | 33
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 22 | 22 | 22 | 22 | 22 | 22 | 21 | 19 | 13 | 0
Total of IBNR liabilities plus expected development on reported claims | 1 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 10 | 11 | 12 | 15 | 17 | 19 | 23 | 23 | 27 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 7 | 7 | 7 | 7 | 6 | 3 | 0 | (2) | (7) |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 15 | 15 | 17 | 20 | 21 | 24 | 26 | 29 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 12 | 12 | 12 | 11 | 11 | 9 | 6 | 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 | 20 | 20 | 21 | 24 | 24 | 25 | 27 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 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 | 62 | 62 | 60 | 60 | 54 | 48 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 49 | 43 | 34 | 28 | 21 | 10 |  |  |  |
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 | 79 | 79 | 75 | 82 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 66 | 59 | 42 | 26 | 9 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 7 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 78 | 80 | 95 | 109 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 52 | 45 | 24 | 8 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 9 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 133 | 137 | 125 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 62 | 37 | 12 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 42 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 166 | 161 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 43 | 13 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 66 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 235 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 18 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 157 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 6,695 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 3,976 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 30 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 2,749 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 245 | 247 | 249 | 251 | 261 | 264 | 264 | 267 | 269 | 270
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 234 | 234 | 232 | 231 | 228 | 217 | 205 | 191 | 157 | $ 81
Total of IBNR liabilities plus expected development on reported claims | 1 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 291 | 298 | 297 | 300 | 304 | 298 | 307 | 314 | 317 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 284 | 284 | 281 | 275 | 269 | 253 | 235 | 199 | $ 105 |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 348 | 352 | 355 | 358 | 360 | 361 | 378 | 386 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 337 | 336 | 327 | 316 | 303 | 289 | 249 | $ 132 |  |
Total of IBNR liabilities plus expected development on reported claims | 11 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 405 | 411 | 411 | 415 | 391 | 396 | 403 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 369 | 366 | 344 | 327 | 306 | 267 | $ 126 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 22 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 388 | 393 | 383 | 388 | 393 | 414 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 335 | 316 | 295 | 269 | 205 | $ 118 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 27 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 518 | 526 | 506 | 511 | 578 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 434 | 396 | 361 | 286 | $ 130 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 44 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 602 | 594 | 594 | 594 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 481 | 420 | 302 | $ 148 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 55 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 956 | 911 | 929 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 606 | 451 | $ 176 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 161 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,238 | 1,310 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 534 | $ 238 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 390 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2024 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,704 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 362 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | $ 1,070 |  |  |  |  |  |  |  |  |

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