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Unpaid losses and loss expenses Unpaid Losses and loss expenses, claims development (Cumulative Net incurred Loss and Allocated Loss Adjustment Expense) (Details) $ in Millions | 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 ($) | Dec. 31, 2012 USD ($) | Dec. 31, 2011 USD ($) | Dec. 31, 2010 USD ($)
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | $ 46,062 |  |  |  |  |  |  |  |  |
North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 11,846 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 5,100 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 2,668 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 9,414 |  |  |  |  |  |  |  |  |
North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 34,245 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 19,320 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 1,522 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 16,447 |  |  |  |  |  |  |  |  |
North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 5,227 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 3,566 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 252 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 1,913 |  |  |  |  |  |  |  |  |
North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 18,124 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 16,376 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 11 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 1,759 |  |  |  |  |  |  |  |  |
North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 24,271 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 21,773 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 27 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 2,525 |  |  |  |  |  |  |  |  |
Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 12,380 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 6,835 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 432 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 5,977 |  |  |  |  |  |  |  |  |
Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 19,023 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 16,743 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 97 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 2,377 |  |  |  |  |  |  |  |  |
Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 3,052 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 2,178 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 303 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 1,177 |  |  |  |  |  |  |  |  |
Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 2,214 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | 1,965 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented | 6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net | 255 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | 999 | $ 1,018 | $ 1,020 | $ 1,028 | $ 1,052 | $ 1,064 | $ 1,065 | $ 1,050 | $ 1,037 | $ 1,049
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 223 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 684 | 666 | 641 | 617 | 592 | 551 | 493 | 411 | 300 | 123
Cumulative Number of Reported Claims | 303,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,983 | 2,993 | 3,105 | 3,125 | 3,247 | 3,416 | 3,556 | 3,597 | 3,579 | 3,574
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 202 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,716 | 2,659 | 2,525 | 2,424 | 2,257 | 1,892 | 1,558 | 1,108 | 611 | 126
Cumulative Number of Reported Claims | 18,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 481 | 484 | 493 | 480 | 478 | 506 | 546 | 601 | 607 | 613
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 16 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 452 | 453 | 449 | 443 | 433 | 392 | 363 | 322 | 236 | 97
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,394 | 1,394 | 1,404 | 1,410 | 1,415 | 1,422 | 1,424 | 1,461 | 1,537 | 1,501
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,391 | 1,391 | 1,395 | 1,394 | 1,391 | 1,382 | 1,357 | 1,320 | 1,222 | 723
Cumulative Number of Reported Claims | 1,057,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,820 | 1,821 | 1,820 | 1,823 | 1,828 | 1,832 | 1,835 | 1,853 | 1,876 | 1,868
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,812 | 1,810 | 1,809 | 1,803 | 1,791 | 1,770 | 1,727 | 1,668 | 1,521 | 1,151
Cumulative Number of Reported Claims | 146,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,149 | 1,142 | 1,136 | 1,141 | 1,265 | 1,316 | 1,379 | 1,308 | 1,263 | 1,183
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 68 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 983 | 946 | 903 | 850 | 801 | 712 | 605 | 462 | 265 | 102
Cumulative Number of Reported Claims | 37,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,582 | 1,584 | 1,582 | 1,599 | 1,612 | 1,626 | 1,632 | 1,643 | 1,669 | 1,647
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,562 | 1,550 | 1,545 | 1,544 | 1,537 | 1,524 | 1,486 | 1,424 | 1,226 | 671
Cumulative Number of Reported Claims | 518,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 373 | 387 | 400 | 414 | 424 | 430 | 441 | 430 | 419 | 399
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 23 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 320 | 315 | 306 | 291 | 274 | 249 | 220 | 179 | 125 | 56
Cumulative Number of Reported Claims | 802 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2010 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 217 | 218 | 219 | 218 | 218 | 216 | 212 | 218 | 228 | 194
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 0 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 214 | 210 | 210 | 207 | 209 | 199 | 193 | 182 | 156 | $ 55
Cumulative Number of Reported Claims | 102 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 988 | 1,009 | 1,012 | 1,022 | 1,053 | 1,049 | 1,046 | 1,030 | 1,037 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 233 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 640 | 616 | 595 | 567 | 533 | 484 | 411 | 294 | 119 |
Cumulative Number of Reported Claims | 286,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,190 | 3,312 | 3,380 | 3,494 | 3,590 | 3,660 | 3,626 | 3,582 | 3,496 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 299 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,824 | 2,738 | 2,657 | 2,474 | 2,212 | 1,803 | 1,208 | 651 | 160 |
Cumulative Number of Reported Claims | 18,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 512 | 510 | 516 | 524 | 533 | 548 | 581 | 589 | 580 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 24 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 486 | 480 | 466 | 461 | 437 | 400 | 341 | 235 | 86 |
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,833 | 1,832 | 1,832 | 1,837 | 1,833 | 1,853 | 1,875 | 1,932 | 1,958 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 10 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,822 | 1,819 | 1,813 | 1,808 | 1,785 | 1,775 | 1,715 | 1,571 | 938 |
Cumulative Number of Reported Claims | 1,051,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,156 | 2,156 | 2,157 | 2,158 | 2,162 | 2,170 | 2,182 | 2,207 | 2,205 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,146 | 2,143 | 2,136 | 2,126 | 2,103 | 2,049 | 1,969 | 1,833 | 1,358 |
Cumulative Number of Reported Claims | 166,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 988 | 991 | 1,042 | 1,054 | 1,117 | 1,200 | 1,210 | 1,218 | 1,211 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 35 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 848 | 815 | 764 | 691 | 612 | 513 | 384 | 240 | 87 |
Cumulative Number of Reported Claims | 37,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,810 | 1,814 | 1,824 | 1,832 | 1,843 | 1,861 | 1,900 | 1,956 | 1,871 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,773 | 1,773 | 1,769 | 1,761 | 1,746 | 1,716 | 1,660 | 1,460 | 758 |
Cumulative Number of Reported Claims | 544,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 401 | 407 | 413 | 417 | 427 | 432 | 428 | 414 | 407 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 27 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 331 | 324 | 311 | 291 | 267 | 236 | 195 | 146 | 70 |
Cumulative Number of Reported Claims | 659 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2011 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 259 | 259 | 259 | 260 | 258 | 258 | 268 | 270 | 269 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 256 | 254 | 253 | 251 | 246 | 228 | 204 | 174 | $ 85 |
Cumulative Number of Reported Claims | 132 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 977 | 986 | 989 | 1,011 | 1,040 | 1,030 | 1,011 | 1,050 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 275 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 592 | 574 | 532 | 486 | 436 | 365 | 271 | 111 |  |
Cumulative Number of Reported Claims | 287,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,231 | 3,326 | 3,422 | 3,520 | 3,560 | 3,609 | 3,624 | 3,548 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 430 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,615 | 2,499 | 2,324 | 2,090 | 1,678 | 1,171 | 655 | 166 |  |
Cumulative Number of Reported Claims | 18,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 507 | 508 | 519 | 520 | 560 | 577 | 605 | 633 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 493 | 486 | 470 | 435 | 386 | 319 | 222 | 69 |  |
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,847 | 1,841 | 1,844 | 1,856 | 1,861 | 1,880 | 1,913 | 2,030 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,839 | 1,813 | 1,819 | 1,792 | 1,764 | 1,696 | 1,575 | 713 |  |
Cumulative Number of Reported Claims | 1,035,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,192 | 2,186 | 2,184 | 2,183 | 2,189 | 2,181 | 2,181 | 2,183 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 20 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,161 | 2,161 | 2,147 | 2,115 | 2,061 | 1,955 | 1,804 | 1,175 |  |
Cumulative Number of Reported Claims | 170,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,255 | 1,265 | 1,285 | 1,294 | 1,297 | 1,279 | 1,217 | 1,246 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 137 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 939 | 897 | 826 | 689 | 577 | 428 | 245 | 74 |  |
Cumulative Number of Reported Claims | 38,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,556 | 1,561 | 1,577 | 1,585 | 1,591 | 1,646 | 1,686 | 1,696 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 14 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,517 | 1,515 | 1,502 | 1,493 | 1,470 | 1,412 | 1,226 | 681 |  |
Cumulative Number of Reported Claims | 556,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 372 | 370 | 371 | 378 | 393 | 390 | 382 | 385 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 10 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 334 | 322 | 307 | 292 | 260 | 221 | 167 | 77 |  |
Cumulative Number of Reported Claims | 457 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 184 | 184 | 187 | 189 | 191 | 200 | 210 | 230 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 180 | 179 | 177 | 172 | 166 | 156 | 130 | $ 45 |  |
Cumulative Number of Reported Claims | 113 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,037 | 1,073 | 1,086 | 1,127 | 1,122 | 1,108 | 1,109 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 309 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 616 | 587 | 553 | 506 | 422 | 286 | 107 |  |  |
Cumulative Number of Reported Claims | 299,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,118 | 3,212 | 3,426 | 3,528 | 3,538 | 3,538 | 3,543 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 500 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,371 | 2,230 | 2,005 | 1,595 | 1,191 | 547 | 130 |  |  |
Cumulative Number of Reported Claims | 17,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 461 | 462 | 468 | 515 | 522 | 530 | 526 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 29 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 418 | 411 | 385 | 348 | 270 | 197 | 69 |  |  |
Cumulative Number of Reported Claims | 17,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,334 | 1,337 | 1,337 | 1,356 | 1,333 | 1,420 | 1,430 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,329 | 1,321 | 1,308 | 1,282 | 1,234 | 1,135 | 649 |  |  |
Cumulative Number of Reported Claims | 1,072,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,938 | 1,931 | 1,918 | 1,894 | 1,890 | 1,882 | 1,854 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 26 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,890 | 1,879 | 1,837 | 1,781 | 1,682 | 1,499 | 1,040 |  |  |
Cumulative Number of Reported Claims | 122,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,136 | 1,193 | 1,226 | 1,272 | 1,229 | 1,233 | 1,237 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 139 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 865 | 798 | 699 | 558 | 414 | 261 | 85 |  |  |
Cumulative Number of Reported Claims | 38,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,609 | 1,621 | 1,651 | 1,656 | 1,703 | 1,770 | 1,778 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 27 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,562 | 1,553 | 1,534 | 1,497 | 1,466 | 1,273 | 698 |  |  |
Cumulative Number of Reported Claims | 574,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 316 | 323 | 330 | 329 | 328 | 326 | 320 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 20 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 268 | 259 | 241 | 222 | 186 | 143 | 65 |  |  |
Cumulative Number of Reported Claims | 341 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 140 | 140 | 143 | 142 | 147 | 159 | 161 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 0 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 135 | 135 | 132 | 129 | 120 | 102 | $ 46 |  |  |
Cumulative Number of Reported Claims | 121 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,100 | 1,163 | 1,215 | 1,217 | 1,201 | 1,207 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 395 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 566 | 532 | 484 | 410 | 295 | 113 |  |  |  |
Cumulative Number of Reported Claims | 336,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,467 | 3,652 | 3,713 | 3,671 | 3,582 | 3,532 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 792 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,440 | 2,200 | 1,802 | 1,249 | 679 | 164 |  |  |  |
Cumulative Number of Reported Claims | 17,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 538 | 555 | 596 | 581 | 583 | 594 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 45 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 473 | 454 | 391 | 317 | 220 | 80 |  |  |  |
Cumulative Number of Reported Claims | 17,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,547 | 1,546 | 1,555 | 1,576 | 1,658 | 1,642 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,543 | 1,528 | 1,502 | 1,481 | 1,370 | 818 |  |  |  |
Cumulative Number of Reported Claims | 1,100,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,143 | 2,156 | 2,142 | 2,189 | 2,203 | 2,202 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 19 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,103 | 2,076 | 2,031 | 1,922 | 1,762 | 1,308 |  |  |  |
Cumulative Number of Reported Claims | 132,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,167 | 1,249 | 1,333 | 1,317 | 1,308 | 1,238 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 208 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 786 | 704 | 591 | 461 | 287 | 111 |  |  |  |
Cumulative Number of Reported Claims | 39,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,804 | 1,814 | 1,851 | 1,862 | 1,920 | 1,852 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 15 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,741 | 1,727 | 1,696 | 1,632 | 1,423 | 758 |  |  |  |
Cumulative Number of Reported Claims | 549,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 346 | 343 | 341 | 338 | 333 | 332 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 39 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 276 | 264 | 248 | 217 | 184 | 91 |  |  |  |
Cumulative Number of Reported Claims | 382 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 180 | 181 | 183 | 180 | 180 | 164 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 171 | 169 | 163 | 152 | 129 | $ 65 |  |  |  |
Cumulative Number of Reported Claims | 101 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,217 | 1,279 | 1,276 | 1,259 | 1,282 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 500 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 564 | 501 | 418 | 301 | 116 |  |  |  |  |
Cumulative Number of Reported Claims | 334,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,939 | 3,971 | 3,814 | 3,705 | 3,556 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1,232 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,289 | 1,854 | 1,205 | 605 | 138 |  |  |  |  |
Cumulative Number of Reported Claims | 19,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 458 | 515 | 501 | 470 | 486 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 51 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 370 | 304 | 214 | 137 | 47 |  |  |  |  |
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,602 | 1,635 | 1,647 | 1,742 | 1,733 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 17 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,570 | 1,554 | 1,486 | 1,341 | 725 |  |  |  |  |
Cumulative Number of Reported Claims | 1,170,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,559 | 2,540 | 2,557 | 2,546 | 2,491 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 30 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,475 | 2,388 | 2,267 | 2,081 | 1,497 |  |  |  |  |
Cumulative Number of Reported Claims | 135,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,286 | 1,311 | 1,288 | 1,259 | 1,164 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 287 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 780 | 661 | 484 | 281 | 86 |  |  |  |  |
Cumulative Number of Reported Claims | 41,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,999 | 2,017 | 2,051 | 2,075 | 1,952 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 38 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,881 | 1,858 | 1,778 | 1,546 | 852 |  |  |  |  |
Cumulative Number of Reported Claims | 571,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 308 | 300 | 299 | 288 | 284 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 33 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 232 | 217 | 191 | 159 | 90 |  |  |  |  |
Cumulative Number of Reported Claims | 298 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 153 | 161 | 161 | 154 | 146 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 146 | 142 | 132 | 103 | $ 56 |  |  |  |  |
Cumulative Number of Reported Claims | 115 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,378 | 1,383 | 1,361 | 1,366 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 673 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 529 | 452 | 326 | 122 |  |  |  |  |  |
Cumulative Number of Reported Claims | 304,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,801 | 3,688 | 3,591 | 3,530 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1,279 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,974 | 1,335 | 662 | 171 |  |  |  |  |  |
Cumulative Number of Reported Claims | 20,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 524 | 527 | 502 | 504 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 136 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 323 | 246 | 145 | 52 |  |  |  |  |  |
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,778 | 1,797 | 1,887 | 1,907 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 16 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,729 | 1,653 | 1,502 | 845 |  |  |  |  |  |
Cumulative Number of Reported Claims | 1,291,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,479 | 2,541 | 2,532 | 2,436 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 78 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,311 | 2,208 | 2,049 | 1,451 |  |  |  |  |  |
Cumulative Number of Reported Claims | 138,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,385 | 1,357 | 1,291 | 1,191 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 428 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 667 | 520 | 316 | 123 |  |  |  |  |  |
Cumulative Number of Reported Claims | 42,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,018 | 2,040 | 2,052 | 2,050 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 17 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,938 | 1,865 | 1,670 | 1,015 |  |  |  |  |  |
Cumulative Number of Reported Claims | 567,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 233 | 234 | 226 | 222 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 30 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 159 | 142 | 113 | 57 |  |  |  |  |  |
Cumulative Number of Reported Claims | 341 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 190 | 188 | 186 | 180 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 12 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 169 | 158 | 131 | $ 56 |  |  |  |  |  |
Cumulative Number of Reported Claims | 182 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,399 | 1,380 | 1,412 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 783 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 437 | 313 | 120 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 339,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,577 | 3,495 | 3,319 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1,818 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,161 | 616 | 161 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 21,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 577 | 566 | 531 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 174 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 312 | 175 | 66 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 16,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,503 | 2,605 | 2,701 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 71 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,301 | 2,085 | 978 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 1,374,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,998 | 3,066 | 3,031 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 171 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,664 | 2,517 | 1,696 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 142,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,335 | 1,286 | 1,185 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 495 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 520 | 314 | 96 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 41,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,220 | 2,238 | 2,198 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 46 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,005 | 1,830 | 1,046 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 577,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 219 | 214 | 213 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 45 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 122 | 100 | 46 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 529 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 453 | 423 | 396 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 10 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 402 | 322 | $ 191 |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 309 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,360 | 1,359 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 788 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 329 | 130 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 362,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,490 | 3,371 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 2,170 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 754 | 189 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 24,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 563 | 535 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 298 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 169 | 74 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 15,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,237 | 2,050 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 182 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,823 | 1,026 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 1,551,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,033 | 3,006 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 295 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 2,545 | 1,924 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 148,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,333 | 1,283 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 789 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 325 | 109 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 40,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,244 | 2,153 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 124 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,726 | 994 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 622,000 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 246 | 244 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 65 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 96 | 41 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 589 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 297 | 285 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | (6) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 257 | $ 94 |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 212 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | North America Commercial P&C Insurance - Workers' Compensation [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,391 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 997 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 143 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 246,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | North America Commercial P&C Insurance - Liability [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 3,449 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 3,005 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 176 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 25,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | North America Commercial P&C Insurance - Other Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 606 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 428 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 70 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 14,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | North America Commercial P&C Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,049 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 587 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,029 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 1,446,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | North America Personal P&C Insurance [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,953 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 725 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,666 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 116,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Overseas General Insurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 1,346 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 1,011 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 122 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 32,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Overseas General Insurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 2,181 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 376 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 1,038 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 608,000 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Global Reinsurance - Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 238 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 130 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 40 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 219 |  |  |  |  |  |  |  |  |
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Global Reinsurance - Non-Casualty [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net | $ 141 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | 73 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net | $ 35 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | 32 |  |  |  |  |  |  |  |  |

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