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v3.22.2

Summary of Significant Accounting Policies - Catastrophe Exposures - Additional Information (Details) - USD ($) $ in Thousands | May 01, 2022 | Jan. 01, 2022
--- | --- | ---
California Earthquake |  |
Accumulated Other Comprehensive Income Loss [Line Items] |  |
Catastrophe reinsurance | $ 750 | $ 600
First-dollar retention | 25 | 25
Outside of California Earthquake |  |
Accumulated Other Comprehensive Income Loss [Line Items] |  |
Catastrophe reinsurance | 775 | 625
First-dollar retention | 25 | 25
Other Perils including Wind |  |
Accumulated Other Comprehensive Income Loss [Line Items] |  |
Catastrophe reinsurance | 625 | 475
First-dollar retention | 25 | 25
Catastrophe |  |
Accumulated Other Comprehensive Income Loss [Line Items] |  |
First-dollar retention | 25 | $ 25
Additional catastrophe reinsurance | $ 150 |

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Balance Type: | debit
Period Type: | duration

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- Definition Catastrophe Reinsurance Amounts. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Represents the amount of first-dollar liability retained by the entity on catastrophe exposures under reinsurance protection. + References No definition available. + Details
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Namespace Prefix: | rli_
Data Type: | xbrli:monetaryItemType
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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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- Details
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