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Historical Loss And LAE Development | 9 Months Ended
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Sep. 30, 2025
Historical Loss And L A E Development Disclosure [Abstract] |
Historical Loss And LAE Development | 3. HISTORICAL LOSS AND LAE DEVELOPMENT ​ The following table is a reconciliation of our unpaid losses and settlement expenses (LAE) for the first nine months of 2025 and 2024: ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 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
​ For the first nine months of 2025, incurred losses and LAE included $74 million of favorable development on prior years’ loss reserves, largely from accident years 2019 through 2022 and 2024. Commercial excess liability, marine, surety, commercial property, general liability and our mortgage reinsurance program were drivers of the favorable development. While no products experienced significant adverse development, auto liability exposures developed adversely for some products, most notably in commercial transportation. ​ For the first nine months of 2024, incurred losses and LAE included $85 million of favorable development on prior years’ loss reserves, largely from accident years 2016, 2017, 2019, 2020, 2022 and 2023. Marine, surety, commercial property, commercial excess liability, general liability, professional services, executive products and personal umbrella were drivers of the favorable development. No products experienced significant adverse development.

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- Definition The entire disclosure for liabilities related to future policy benefits and unpaid claims and claim adjustments. + 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org/944-40/tableOfContent + Details
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