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Guarantees and Contingent Liabilities (Details) | 9 Months Ended
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Sep. 30, 2018 USD ($) appeal
Proceedings: |
Number of appeals | appeal | 3
Minimum |
Proceedings: |
Loss contingencies, reasonably possible pretax loss exposure in excess of the amount accrued | $ 0
Maximum |
Proceedings: |
Loss contingencies, reasonably possible pretax loss exposure in excess of the amount accrued | 115,000,000
Texas Windstorm Insurance Association |
Proceedings: |
Loss contingency, loss accrual | $ 37,000,000

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- Definition Estimate of the reasonably possible pretax loss exposure in excess of the amount accrued for the entity's lawsuits, regulatory inquiries and other legal proceedings. + References No definition available. + Details
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- Definition Amount of loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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