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Short Duration Contracts - Claims development - Reinsurance (Details) - USD ($) $ in Millions | 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 | Dec. 31, 2014
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | $ 15,700 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 3,801 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 1,405 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 310 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 2,706 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 241 | $ 234 | $ 234 | $ 237 | $ 237 | $ 227 | $ 230 | $ 217 | $ 220 | $ 215
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 160 | 153 | 145 | 134 | 114 | 91 | 63 | 41 | 16 | 4
Total of IBNR liabilities plus expected development on reported claims | 33 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 260 | 251 | 249 | 246 | 239 | 235 | 228 | 219 | 220 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 170 | 152 | 137 | 120 | 96 | 71 | 47 | 20 | 4 |
Total of IBNR liabilities plus expected development on reported claims | 44 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 281 | 272 | 268 | 269 | 262 | 247 | 224 | 212 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 172 | 157 | 132 | 113 | 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 | 330 | 316 | 309 | 297 | 270 | 254 | 267 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 189 | 164 | 137 | 113 | 64 | 30 | 6 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 53 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 308 | 298 | 286 | 281 | 289 | 276 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 182 | 155 | 129 | 106 | 31 | 8 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 50 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 400 | 379 | 367 | 341 | 330 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 219 | 130 | 97 | 58 | 16 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 84 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 372 | 354 | 371 | 382 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 132 | 90 | 50 | 18 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 163 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 425 | 434 | 439 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 102 | 53 | 15 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 205 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 527 | 547 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 61 | 18 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 390 |  |  |  |  |  |  |  |  |
Reinsurance | Casualty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 657 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 18 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 568 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,229 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 668 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 2 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 563 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 19 | 19 | 19 | 19 | 20 | 20 | 22 | 25 | 30 | 44
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 19 | 19 | 19 | 19 | 19 | 18 | 19 | 18 | 20 | 14
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 3 | 3 | 3 | 3 | 4 | 6 | 12 | 18 | 33 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 2 | 2 | 2 | 2 | 2 | 2 | 2 | (2) | (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 | 5 | 5 | 6 | 7 | 9 | 13 | 17 | 24 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 3 | 3 | 3 | 2 | 3 | 2 | 2 | (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 | 22 | 21 | 24 | 36 | 50 | 54 | 86 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 17 | 16 | 14 | 27 | 37 | 32 | 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 | 5 | 8 | 17 | 30 | 49 | 71 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (9) | (11) | (13) | 16 | 5 | 27 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | (7) | 1 | 9 | 10 | 20 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | (13) | (14) | 11 | 7 | 4 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 2 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 326 | 337 | 333 | 269 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 249 | 207 | 158 | 56 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 17 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 294 | 308 | 314 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 222 | 171 | 65 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 13 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 295 | 303 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 169 | 70 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 41 |  |  |  |  |  |  |  |  |
Reinsurance | Property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 267 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 9 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 76 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 3,285 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 2,029 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 5 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 1,261 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 79 | 79 | 80 | 82 | 84 | 88 | 90 | 98 | 117 | 142
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 78 | 78 | 78 | 78 | 78 | 78 | 76 | 71 | 62 | 23
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 167 | 167 | 173 | 176 | 187 | 188 | 184 | 188 | 214 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 160 | 159 | 159 | 159 | 165 | 160 | 149 | 119 | 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 | 130 | 130 | 136 | 139 | 135 | 137 | 145 | 175 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 115 | 115 | 114 | 111 | 104 | 98 | 94 | 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 | 202 | 206 | 214 | 230 | 237 | 250 | 268 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 186 | 182 | 179 | 164 | 156 | 125 | 28 |  |  |
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 | 203 | 202 | 212 | 235 | 239 | 224 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 177 | 175 | 167 | 152 | 108 | 30 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 7 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 190 | 190 | 195 | 206 | 216 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 169 | 162 | 150 | 124 | 43 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 320 | 320 | 340 | 368 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 267 | 243 | 207 | 101 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 15 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 491 | 497 | 545 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 364 | 270 | 136 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 38 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 668 | 742 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 361 | 143 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 119 |  |  |  |  |  |  |  |  |
Reinsurance | Property excluding property catastrophe | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 835 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 152 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 414 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 611 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 271 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 17 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 357 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 18 | 19 | 22 | 22 | 23 | 23 | 25 | 27 | 29 | 31
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 17 | 17 | 16 | 16 | 15 | 15 | 12 | 11 | 8 | 4
Total of IBNR liabilities plus expected development on reported claims | 0 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 24 | 25 | 27 | 28 | 30 | 31 | 32 | 37 | 33 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 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 | 11 | 12 | 15 | 17 | 19 | 23 | 23 | 27 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 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 | 17 | 20 | 21 | 24 | 26 | 29 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 12 | 12 | 12 | 11 | 9 | 6 | 2 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 21 | 21 | 24 | 24 | 26 | 27 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 15 | 14 | 13 | 11 | 7 | 2 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 62 | 61 | 60 | 55 | 48 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 43 | 35 | 29 | 21 | 11 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 9 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 80 | 79 | 76 | 83 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 60 | 42 | 26 | 9 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 10 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 81 | 96 | 110 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 45 | 24 | 8 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 18 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 138 | 126 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 37 | 12 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 59 |  |  |  |  |  |  |  |  |
Reinsurance | Marine and aviation | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 161 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 13 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 127 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 5,483 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 3,408 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 19 |  |  |  |  |  |  |  |  |
Liabilities for losses and loss adjustment expenses, net of reinsurance | 2,094 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 295 | 296 | 298 | 304 | 308 | 307 | 312 | 318 | 316 | 337
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 282 | 280 | 278 | 275 | 271 | 258 | 248 | 229 | 186 | $ 96
Total of IBNR liabilities plus expected development on reported claims | 1 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 255 | 258 | 259 | 270 | 273 | 273 | 276 | 278 | 280 |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 241 | 240 | 239 | 236 | 224 | 211 | 197 | 162 | $ 83 |
Total of IBNR liabilities plus expected development on reported claims | 3 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 307 | 306 | 309 | 314 | 307 | 316 | 323 | 326 |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 293 | 289 | 283 | 277 | 261 | 242 | 205 | $ 108 |  |
Total of IBNR liabilities plus expected development on reported claims | 6 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 363 | 366 | 370 | 372 | 372 | 390 | 398 |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 346 | 337 | 326 | 313 | 298 | 256 | $ 136 |  |  |
Total of IBNR liabilities plus expected development on reported claims | 15 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 423 | 424 | 428 | 404 | 409 | 416 |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 376 | 353 | 336 | 315 | 276 | $ 130 |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 29 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 405 | 395 | 400 | 406 | 427 |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 325 | 303 | 277 | 211 | $ 121 |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 40 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 539 | 519 | 524 | 593 |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 405 | 370 | 293 | $ 134 |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 61 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 613 | 611 | 610 |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 432 | 311 | $ 152 |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 80 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 935 | 953 |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 464 | $ 182 |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | 225 |  |  |  |  |  |  |  |  |
Reinsurance | Other specialty | 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred losses and allocated loss adjustment expenses, net of reinsurance | 1,348 |  |  |  |  |  |  |  |  |
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance | 244 |  |  |  |  |  |  |  |  |
Total of IBNR liabilities plus expected development on reported claims | $ 817 |  |  |  |  |  |  |  |  |

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