XML 32 R21.htm IDEA: XBRL DOCUMENT
v3.25.3

Historical Loss And LAE Development (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2025
Historical Loss And L A E Development Disclosure [Abstract] |
Schedule of Reconciliation of Unpaid Losses and Settlement Expenses (LAE) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Nine Months
​ | ​ | Ended September 30,
(in thousands) |  | 2025 |  | 2024
Unpaid losses and LAE at beginning of year | ​ | ​ | ​ | ​ | ​ | ​
Gross | ​ | $ | 2,693,470 | ​ | $ | 2,446,025
Ceded | ​ | ​ | (755,425) | ​ | ​ | (757,349)
Net | ​ | $ | 1,938,045 | ​ | $ | 1,688,676
​ | ​ | ​ | ​ | ​ | ​ | ​
Increase (decrease) in incurred losses and LAE | ​ | ​ | ​ | ​ | ​ | ​
Current accident year | ​ | $ | 623,926 | ​ | $ | 599,183
Prior accident years | ​ | ​ | (74,112) | ​ | ​ | (85,442)
Total incurred | ​ | $ | 549,814 | ​ | $ | 513,741
​ | ​ | ​ | ​ | ​ | ​ | ​
Loss and LAE payments for claims incurred | ​ | ​ | ​ | ​ | ​ | ​
Current accident year | ​ | $ | (74,868) | ​ | $ | (76,148)
Prior accident years | ​ | ​ | (309,548) | ​ | ​ | (273,868)
Total paid | ​ | $ | (384,416) | ​ | $ | (350,016)
​ | ​ | ​ | ​ | ​ | ​ | ​
Net unpaid losses and LAE at September 30, | ​ | $ | 2,103,443 | ​ | $ | 1,852,401
​ | ​ | ​ | ​ | ​ | ​ | ​
Unpaid losses and LAE at September 30, | ​ | ​ | ​ | ​ | ​ | ​
Gross | ​ | $ | 2,873,054 | ​ | $ | 2,611,941
Ceded | ​ | ​ | (769,611) | ​ | ​ | (759,540)
Net | ​ | $ | 2,103,443 | ​ | $ | 1,852,401

X
- Definition Historical loss and LAE development disclosure. + References No definition available. + Details
Name: | rli_HistoricalLossAndLAEDevelopmentDisclosureAbstract
Namespace Prefix: | rli_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the activity in the reserve for settling insured claims and expenses incurred in the claims settlement process for the period. The estimated liability includes the amount of money that will be required for future payments of (a) claims that have been reported to the insurer, (b) claims related to insured events that have occurred but that have not been reported to the insurer as of the date the liability is estimated, and (c) claim adjustment expenses. Claim adjustment expenses include costs incurred in the claim settlement process such as legal fees; outside adjuster fees; and costs to record, process, and adjust claims. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
Name: | us-gaap_ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration