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Unpaid losses and loss expenses Unpaid losses and loss expenses (Supplementary PPD) (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($)
North America Commercial P&C Insurance - Workers' Compensation [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | $ (304)
North America Commercial P&C Insurance - Workers' Compensation [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (113)
North America Commercial P&C Insurance - Workers' Compensation [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (191)
North America Commercial P&C Insurance - Liability [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 222
North America Commercial P&C Insurance - Liability [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 47
North America Commercial P&C Insurance - Liability [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 175
North America Commercial P&C Insurance - Other Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 93
North America Commercial P&C Insurance - Other Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (6)
North America Commercial P&C Insurance - Other Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 99
North America Commercial P&C Insurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (381)
North America Commercial P&C Insurance - Non-Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (4)
North America Commercial P&C Insurance - Non-Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (377)
North America Personal P&C Insurance [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (128)
North America Personal P&C Insurance [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 3
North America Personal P&C Insurance [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (131)
Overseas General Insurance - Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (48)
Overseas General Insurance - Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (22)
Overseas General Insurance - Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (26)
Overseas General Insurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (268)
Overseas General Insurance - Non-Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (4)
Overseas General Insurance - Non-Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (264)
Global Reinsurance - Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 6
Global Reinsurance - Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | (16)
Global Reinsurance - Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 22
Global Reinsurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (42)
Global Reinsurance - Non-Casualty [Member] | Accident years prior to 2014 |
Supplementary PPD [Line Items] |
Short-Duration PPD | 0
Global Reinsurance - Non-Casualty [Member] | Accident years 2014 - 2023 |
Supplementary PPD [Line Items] |
Short-Duration PPD | $ (42)

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