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Reinsurance - Per Occurrence Excess Agreement (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) layer reinstatement
Reinsurance Retention Policy [Line Items] |
Retention amount for catastrophe reinsurance agreement contracts | $ 500
Catastrophe Reinsurance First Five Layers |
Reinsurance Retention Policy [Line Items] |
Number of layers subject to reinstatement in which catastrophe reinsurance agreement contracts are placed | layer | 3
Retention percentage of reinsurance limit | 31.70%
Catastrophe Reinsurance Sixth Layer |
Reinsurance Retention Policy [Line Items] |
Retention percentage of reinsurance limit | 95.00%
Catastrophe Reinsurance Layer, One to Six |
Reinsurance Retention Policy [Line Items] |
Limit of aggregate losses under aggregate excess agreement | $ 3,070
Catastrophe Reinsurance Eight Layer |
Reinsurance Retention Policy [Line Items] |
Retention percentage of reinsurance limit | 29.37%
Catastrophe reinsurance aggregate annual loss limit | $ 446
Catastrophe Reinsurance, Six And Eight Layer |
Reinsurance Retention Policy [Line Items] |
Number of reinstatements each year for each contract | reinstatement | 1
Term of catastrophe reinsurance agreement contract | 7 years
Catastrophe Reinsurance, Eight And Nine Layer |
Reinsurance Retention Policy [Line Items] |
Retention percentage of reinsurance limit | 100.00%
Limit of aggregate losses under aggregate excess agreement | $ 25
Retention amount for catastrophe reinsurance agreement contracts | 2,750
Catastrophe reinsurance aggregate annual loss limit | $ 1,670
Reinsured risk, percentage | 5.00%

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- Definition Represents the retention percentage of annual coverage limit provided by the insurance arrangement for catastrophe claims. + References No definition available. + Details
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Period Type: | duration

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- Definition Represents the number of reinstatements each year for each contract. + References No definition available. + Details
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- Definition Catastrophe Reinsurance Aggregate Annual Loss Limit + References No definition available. + Details
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- Definition The limit of aggregated losses per contract year beyond which coverage provided by an aggregate excess agreement applies. + References No definition available. + Details
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- Definition Represents the number of layers subject to reinstatement in which catastrophe reinsurance agreement contracts are placed. + References No definition available. + Details
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Data Type: | xbrli:integerItemType
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- Definition Represents the period of catastrophe reinsurance agreement contract. + References No definition available. + Details
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Balance Type: | na
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- Definition Represents the retention amount of catastrophe reinsurance agreement contracts. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Percentage of risk reinsured on insurance products per entity policy. + References No definition available. + Details
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- Details
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