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v3.25.2

General - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Mar. 31, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Potentially dilutive securities (in shares) | 0 |  | 0 | 0 | 0 |
Dividends declared and paid (in dollars per share) | $ 0.3175 |  | $ 0.3175 | $ 0.6350 | $ 0.6350 |
Policy acquisition costs | $ 227,880,000 |  | $ 203,682,000 | $ 456,601,000 | $ 399,722,000 |
Advertising expenses | 7,400,000 |  | 3,900,000 | 12,900,000 | 7,200,000 |
Gain (loss) on sale of fixed assets |  |  |  | 2,691,000 | (71,000) |
Ceded premiums earned | 54,400,000 |  | 31,400,000 | 161,100,000 | 62,500,000 |
Losses and loss adjustment expenses, ceded | 400,000 |  | (100,000) | 1,292,900,000 | (900,000) |
Revenue from contract with customer | 6,800,000 |  | 6,000,000.0 | 13,900,000 | 11,700,000 |
Cost of goods and services sold | 3,600,000 |  | 3,200,000 | 7,200,000 | 6,400,000 |
Contract with customer, asset | 0 |  |  | 0 |  | $ 0
Contract with customer, liability | 0 |  |  | 0 |  | 0
Revenue, remaining performance obligation | 0 |  |  | 0 |  | $ 0
Accrued interest receivable considered uncollectible or written off |  |  |  | 0 | 0 |
Reinsurance Contract [Axis]: 100% Reinsurance Limit Used |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Ceded premiums earned | 0 | $ 52,000,000 |  | 52,000,000 |  |
Reinsurance Contract [Axis]: Catastrophe Participation Reinsurance Contract (the "Contract") |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Reinsurance reimbursable amount | 30,000,000 |  |  | $ 30,000,000 |  |
Reinsurance retention policy, threshold loss ratio |  |  |  | 73.50% |  |
Reinsurance Contract [Axis]: Catastrophe Reinsurance Treaty (the "Treaty") |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Reinsurance retention policy, excess retention, amount reinsured |  |  |  | $ 2,140,000,000 |  |
Reinsurance policy, amount retained |  |  |  | 200,000,000 |  |
Reinsurance Contract [Axis]: Pro-Forma, $0 Reinsurance Limit |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Ceded premiums earned | 26,000,000 | $ 26,000,000 |  | 52,000,000 |  |
Reinsurance Contract [Axis]: Property Quota Share Reinsurance Contract ("Quota Share") |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Assumed maximum possible loss | 32,000,000 |  |  | 32,000,000 |  |
Assumed premium written |  |  |  | 11,000,000 |  |
Folsom, California Office Building | Disposal Group, Held-for-sale, Not Discontinued Operations |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Gain (loss) as a result of the held-for-sale classification |  |  | $ (5,400,000) |  | $ (5,400,000) |
Folsom, California Office Building | Disposal Group, Disposed of by Sale, Not Discontinued Operations |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |
Sale price of fixed asset | 13,000,000.0 |  |  | 13,000,000.0 |  |
Gain (loss) on sale of fixed assets | $ 2,700,000 |  |  | $ 2,700,000 |  |

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