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Reinsurance - Quota Share Transactions Terms (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2024 | Sep. 30, 2024
2020 QSR and 2021 QSR - 2021 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 17.50%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 61.90%
2021 QSR and 2022 QSR - 2021 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 12.50%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 57.50%
2021 QSR and 2022 QSR - 2022 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 57.50%
Cede rate, option 1 (as a percent) |  | 12.50%
Cede rate, option 2 (as a percent) |  | 10.00%
2022 QSR and 2023 QSR - 2022 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 62.00%
Cede rate, option 1 (as a percent) |  | 12.50%
Cede rate, option 2 (as a percent) |  | 10.00%
2022 QSR and 2023 QSR - 2023 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 62.00%
Cede rate, option 1 (as a percent) |  | 12.50%
Cede rate, option 2 (as a percent) |  | 10.00%
2023 QSR - 2023 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 10.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 58.50%
Cede rate, option 1 (as a percent) |  | 8.00%
Cede rate, option 2 (as a percent) |  | 7.00%
2024 QSR - 2024 NIW |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 30.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 56.00%
Cede rate, option 1 (as a percent) |  | 23.00%
Cede rate, option 2 (as a percent) |  | 15.00%
Credit Union QSR Transaction |  |
Effects of Reinsurance [Line Items] |  |
Quota Share % |  | 65.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) |  | 50.00%
Forecast | Quota Share Reinsurance Transaction, 2021 |  |
Effects of Reinsurance [Line Items] |  |
Contingent termination fee | $ 8 |

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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option Two + References No definition available. + Details
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