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Reinsurance and Indemnification - 2018-1 Excess Catastrophe Reinsurance Contract (Details) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2019 USD ($) state | Mar. 31, 2019 USD ($)
Reinsurance Retention Policy [Line Items] |  |  |
Limit of aggregate losses under aggregate excess agreement |  | $ 3,400 |
2018-1 Excess Catastrophe Reinsurance Contract |  |  |
Reinsurance Retention Policy [Line Items] |  |  |
Number of states covered under reinsurance agreement | state |  | 49 |
Limit of aggregate losses under aggregate excess agreement | $ 500 | $ 500 | $ 500
Term of catastrophe reinsurance agreement contract |  | 4 years |
Retention percentage of reinsurance limit |  | 100.00% | 100.00%
Minimum | 2018-1 Excess Catastrophe Reinsurance Contract |  |  |
Reinsurance Retention Policy [Line Items] |  |  |
Retention amount for catastrophe reinsurance agreement contracts |  | $ 3,940 | $ 4,360
Maximum | 2018-1 Excess Catastrophe Reinsurance Contract |  |  |
Reinsurance Retention Policy [Line Items] |  |  |
Retention amount for catastrophe reinsurance agreement contracts |  | $ 4,440 | $ 4,860

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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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- 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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Data Type: | xbrli:monetaryItemType
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- Definition Represents the period of catastrophe reinsurance agreement contract. + References No definition available. + Details
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- Definition Represents the retention amount of catastrophe reinsurance agreement contracts. + References No definition available. + Details
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- Definition Represents the number of states covered under the reinsurance agreement. + References No definition available. + Details
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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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- Details
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- Details
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- Details
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