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Insurance - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Other lines | Property and Casualty Insurance |  |  |  |
Insurance [Line Items] |  |  |  |
Special charges to increase asbestos and environmental reserves | $ 18 | $ 89 | $ 18 | $ 89

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- Definition Special charges to increase asbestos and environmental reserves. + References No definition available. + Details
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- Details
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