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Unpaid losses and loss expenses Unpaid losses and loss expenses (Details) (Supplementary PPD) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($)
North America Commercial P&C Insurance - Workers' Compensation [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | $ (155)
North America Commercial P&C Insurance - Workers' Compensation [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (73)
North America Commercial P&C Insurance - Liability [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (141)
North America Commercial P&C Insurance - Liability [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (3)
North America Commercial P&C Insurance - Other Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 20
North America Commercial P&C Insurance - Other Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 14
North America Commercial P&C Insurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (224)
North America Commercial P&C Insurance - Non-Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (1)
North America Personal P&C Insurance [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 47
North America Personal P&C Insurance [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (7)
Overseas General Insurance - Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (64)
Overseas General Insurance - Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (55)
Overseas General Insurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (109)
Overseas General Insurance - Non-Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (11)
Global Reinsurance - Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (73)
Global Reinsurance - Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | (48)
Global Reinsurance - Non-Casualty [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | 18
Global Reinsurance - Non-Casualty [Member] | prior to 2009 [Member] |
Supplementary PPD [Line Items] |
Short-Duration PPD | $ (2)

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- Details
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