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Property and Casualty Insurance Activity - Schedule of Material Terms for Reinsurance Treaties (Details) $ in Thousands | 3 Months Ended | 4 Months Ended | 6 Months Ended | 7 Months Ended | 9 Months Ended | 12 Months Ended | 18 Months Ended
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Dec. 31, 2025 USD ($) | Apr. 30, 2025 USD ($) | Jun. 30, 2026 USD ($) | Dec. 31, 2025 USD ($) | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Jun. 30, 2024 USD ($) | Apr. 30, 2026 USD ($) | Apr. 30, 2025 USD ($) | Sep. 30, 2025 USD ($) h | Jun. 30, 2026 USD ($) | Dec. 31, 2025 | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jun. 30, 2025 USD ($)
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Single risk coverage |  |  |  |  |  |  |  |  |  | $ 9,000 |  |  |  |  |  |
Catastrophe coverage, multiple of per occurrence limitation |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |
Catastrophe coverage, except for one occurrence limitation |  |  |  |  |  |  |  |  |  | 80.00% |  |  |  |  |  |
Catastrophic coverage, first layer |  |  |  |  |  |  |  |  |  | $ 5,000 |  |  |  |  |  |
Excess of catastrophic coverage, first layer |  |  |  |  |  |  |  |  |  | $ 5,000 |  |  |  |  |  |
Catastrophe coverage, one occurrence limitation |  |  |  |  |  |  |  |  |  | 52.00% |  |  |  |  |  |
Catastrophic coverage, top layer |  |  |  |  |  |  |  |  |  | $ 240,000 |  |  |  |  |  |
Excess of catastrophic coverage, top layer |  |  |  |  |  |  |  |  |  | $ 200,000 |  |  |  |  |  |
Catastrophe coverage, number of consecutive hours | h |  |  |  |  |  |  |  |  |  | 168 |  |  |  |  |  |
Reinstatement of premium protection, catastrophe coverage |  |  |  |  |  |  |  |  | $ 4,500 |  |  |  | $ 50,000 |  |  |
Excess of catastrophe coverage |  |  |  |  |  |  |  |  | $ 5,500 |  |  |  | $ 10,000 |  |  |
Underlying XOL treaty, reinsurance coverage (percent) |  |  |  |  |  |  |  |  | 71.00% |  |  |  |  | 50.00% |  | 50.00%
Reinstatement of premium protection |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400
Reinstatement of premium protection, excluded amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 600
Risk retention amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 730 | $ 530
Catastrophe reinsurance coverage, (percent) |  |  |  |  |  |  |  |  | 71.00% |  |  |  |  |  |  |
Limited retention |  | $ 5,200 |  |  |  |  |  |  |  |  |  |  |  | $ 4,800 |  |
Underlying XOL treaty, excess of loss coverage amount |  |  |  |  |  |  |  |  | $ 4,500 |  |  |  |  | 400 |  |
Underlying XOL treaty, excess of loss coverage excluded amount |  |  |  |  |  |  |  |  | $ 5,500 |  |  |  |  | $ 600 |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Direct loss |  |  |  |  |  |  |  |  |  | $ 3,500 |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Direct loss |  |  |  |  |  |  |  |  |  | $ 9,000 |  |  |  |  |  |
Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Catastrophic coverage, first layer |  |  |  |  |  |  |  |  |  |  | $ 5,000 |  |  |  |  |
Excess of catastrophic coverage, first layer |  |  |  |  |  |  |  |  |  |  | 5,000 |  |  |  |  |
Reinstatement of premium protection, catastrophe coverage |  |  |  |  |  |  |  |  |  |  | 50,000 |  |  |  |  |
Excess of catastrophe coverage |  |  |  |  |  |  |  |  |  |  | $ 10,000 |  |  |  |  |
Underlying XOL treaty, reinsurance coverage (percent) |  |  |  |  |  |  |  | 90.00% |  |  | 50.00% |  |  |  |  |
Risk retention amount |  |  |  | $ 640 |  |  |  |  |  |  | $ 715 |  |  |  |  |
Underlying XOL treaty, reinsurance coverage, layer one (percent) |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |
Reinstatement of premium protection, layer one |  |  |  |  |  |  |  |  |  |  | $ 250 |  |  |  |  |
Reinstatement of premium protection, layer one, excluded amount |  |  |  |  |  |  |  |  |  |  | $ 750 |  |  |  |  |
Underlying XOL treaty, reinsurance coverage, layer two (percent) |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |
Reinstatement of premium protection, layer two, excluded amount |  |  |  |  |  |  |  |  |  |  | $ 1,000 |  |  |  |  |
Reinstatement of premium protection, layer two |  |  |  |  |  |  |  |  |  |  | $ 9,000 |  |  |  |  |
Catastrophe, first layer coverage (percent) |  |  |  |  |  |  |  |  |  |  | 80.00% |  |  |  |  |
Catastrophe coverage, remaining (in percent) |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |
Catastrophe coverage, remaining layer |  |  |  |  |  |  |  |  |  |  | $ 430,000 |  |  |  |  |
Excess of catastrophe coverage, remaining |  |  |  |  |  |  |  |  |  |  | 10,000 |  |  |  |  |
Limited retention | $ 3,900 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Underlying XOL treaty, excess of loss coverage amount |  |  |  |  |  |  |  | $ 5,000 |  |  | 250 |  |  |  |  |
Underlying XOL treaty, excess of loss coverage excluded amount |  |  |  |  |  |  |  | $ 5,000 |  |  | $ 750 |  |  |  |  |
Catastrophe Reinsurance: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial loss subject to personal lines quota share treaty |  |  |  |  | $ 10,000 | $ 10,000 | $ 10,000 |  |  |  |  |  |  |  |  |
Risk retained per catastrophe occurrence |  |  |  |  | 4,250 | 4,750 | 9,500 |  |  |  |  |  |  |  |  |
Catastrophe loss coverage |  |  |  |  | $ 275,000 | $ 275,000 | $ 315,000 |  |  |  |  |  |  |  |  |
Reinstatement premium protection |  |  |  |  | Yes | Yes | Yes |  |  |  |  |  |  |  |  |
Catastrophe Reinsurance: | Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial loss subject to personal lines quota share treaty |  |  |  | 10,000 |  |  |  |  |  |  |  |  |  |  |  |
Risk retained per catastrophe occurrence |  |  | $ 6,000 | 5,000 |  |  |  |  |  |  |  |  |  |  |  |
Catastrophe loss coverage |  |  | $ 434,000 | $ 435,000 |  |  |  |  |  |  |  |  |  |  |  |
Reinstatement premium protection |  |  | Yes | Yes |  |  |  |  |  |  |  |  |  |  |  |
Personal Lines: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quota share treaty percent ceded |  |  |  |  | 16.00% | 27.00% | 27.00% |  |  |  |  |  |  | 27.00% |  |
Risk retained on initial $1,000,000 of losses |  |  |  |  | $ 840 | $ 730 | $ 730 |  |  |  |  |  |  |  |  |
Losses per occurrence subject to quota share reinsurance coverage |  |  |  |  | 1,000 | 1,000 | 1,000 |  |  |  |  |  |  |  |  |
Excess of loss coverage and facultative facility coverage |  |  |  |  | 8,400 | 8,400 | 8,400 |  |  |  |  |  |  |  |  |
in excess of 1 |  |  |  |  | 600 | 600 | 600 |  |  |  |  |  |  |  |  |
Total reinsurance coverage per occurrence |  |  |  |  | 8,360 | 8,470 | 8,470 |  |  |  |  |  |  |  |  |
Losses per occurrence subject to reinsurance coverage |  |  |  |  | $ 9,000 | $ 9,000 | $ 9,000 |  |  |  |  |  |  |  |  |
Quota share treaty percent excluded from percent ceded |  |  |  |  |  |  |  |  |  |  |  |  |  | 22.00% |  |
Personal Lines: | Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Quota share treaty percent ceded |  |  |  | 16.00% |  |  |  |  |  |  |  | 16.00% |  |  |  |
Risk retained on initial $1,000,000 of losses |  |  |  | $ 840 |  |  |  |  |  |  |  |  |  |  |  |
Losses per occurrence subject to quota share reinsurance coverage |  |  |  | 1,000 |  |  |  |  |  |  |  |  |  |  |  |
Excess of loss coverage and facultative facility coverage |  |  | $ 8,250 | 8,250 |  |  |  |  |  |  |  |  |  |  |  |
in excess of 1 |  |  | 750 | 750 |  |  |  |  |  |  |  |  |  |  |  |
Total reinsurance coverage per occurrence |  |  | 8,125 | 8,285 |  |  |  |  |  |  |  |  |  |  |  |
Losses per occurrence subject to reinsurance coverage |  |  | $ 9,000 | $ 9,000 |  |  |  |  |  |  |  |  |  |  |  |
Quota share treaty percent excluded from percent ceded |  |  |  |  |  |  |  |  |  |  |  | 6.00% |  |  |  |

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