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Reinsurance (Ceded earned premiums to GEP & Assumed earned premiums to NEP) (Details) | 3 Months Ended | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |
Percentage of ceded earned premiums to gross earned premiums | 53.00% | 45.00% | 47.00% | 42.00%
Percentage of assumed earned premiums to net earned premiums | 71.00% | 44.00% | 47.00% | 33.00%

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