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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit Reserves (International - Hardy - Net Incurred Claims and Allocated Claim Adjustment Expenses) (Details) - International $ in Millions | Dec. 31, 2022 USD ($) claim | Dec. 31, 2021 USD ($) | 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 ($) | Dec. 31, 2013 USD ($)
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Hardy |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 2,016 |  |  |  |  |  |  |  |  |
IBNR | 349 |  |  |  |  |  |  |  |  |
Hardy | 2013 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | 144 | $ 141 | $ 142 | $ 142 | $ 141 | $ 138 | $ 137 | $ 136 | $ 143 | $ 127
IBNR | $ 3 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 7,904,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 164 | 165 | 167 | 169 | 168 | 167 | 173 | 180 | 182 |
IBNR | $ (4) |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 8,530,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 177 | 175 | 174 | 172 | 174 | 174 | 175 | 186 |  |
IBNR | $ (2) |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 9,722,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 216 | 215 | 222 | 220 | 231 | 240 | 224 |  |  |
IBNR | $ 3 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 10,834,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 249 | 249 | 242 | 241 | 248 | 240 |  |  |  |
IBNR | $ 5 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 13,204,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 303 | 303 | 298 | 295 | 264 |  |  |  |  |
IBNR | $ 26 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 15,185,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 221 | 214 | 219 | 216 |  |  |  |  |  |
IBNR | $ 37 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 11,374,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 191 | 197 | 206 |  |  |  |  |  |  |
IBNR | $ 62 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 6,699,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 164 | 174 |  |  |  |  |  |  |  |
IBNR | $ 83 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 3,384,000,000 |  |  |  |  |  |  |  |  |
Hardy | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 187 |  |  |  |  |  |  |  |  |
IBNR | $ 136 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 1,279,000,000 |  |  |  |  |  |  |  |  |
Excluding Hardy |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 3,309 |  |  |  |  |  |  |  |  |
IBNR | 901 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2013 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | 235 | 234 | 231 | 235 | 243 | 250 | 255 | 274 | 281 | $ 279
IBNR | $ 11 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 23,971 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 279 | 273 | 282 | 281 | 264 | 271 | 282 | 283 | $ 268 |
IBNR | $ 13 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 24,962 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 277 | 277 | 275 | 273 | 278 | 294 | 295 | $ 280 |  |
IBNR | $ 22 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 23,372 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 283 | 281 | 268 | 277 | 279 | 292 | $ 275 |  |  |
IBNR | $ 29 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 17,813 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 348 | 359 | 364 | 371 | 351 | $ 290 |  |  |  |
IBNR | $ 57 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 18,498 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 390 | 378 | 379 | 374 | $ 357 |  |  |  |  |
IBNR | $ 67 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 20,849 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 348 | 341 | 344 | $ 331 |  |  |  |  |  |
IBNR | $ 69 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 18,354 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 350 | 360 | $ 368 |  |  |  |  |  |  |
IBNR | $ 138 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 14,952 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 385 | $ 396 |  |  |  |  |  |  |  |
IBNR | $ 201 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 13,580 |  |  |  |  |  |  |  |  |
Excluding Hardy | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expense, net | $ 414 |  |  |  |  |  |  |  |  |
IBNR | $ 294 |  |  |  |  |  |  |  |  |
Cumulative Number of Claims | claim | 8,320 |  |  |  |  |  |  |  |  |

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