Reinsurance - Quota Share Transactions Terms (Details)	3 Months Ended
Mar. 31, 2026
2020 QSR and 2021 QSR
Effects of Reinsurance [Line Items]
Quota Share %	14.80%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	69.00%
Optional Reduced Quota Shares %, option 1	12.30%
Optional Reduced Quota Shares %, option 2	10.00%
2021 QSR and 2022 QSR
Effects of Reinsurance [Line Items]
Quota Share %	11.10%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	69.00%
Optional Reduced Quota Shares %, option 1	9.40%
Optional Reduced Quota Shares %, option 2	7.00%
2021 QSR and 2022 QSR
Effects of Reinsurance [Line Items]
Quota Share %	13.80%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	67.50%
Optional Reduced Quota Shares %, option 1	11.50%
Optional Reduced Quota Shares %, option 2	9.20%
2022 QSR and 2023 QSR
Effects of Reinsurance [Line Items]
Quota Share %	14.50%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	67.50%
Optional Reduced Quota Shares %, option 1	12.10%
Optional Reduced Quota Shares %, option 2	9.70%
2022 QSR and 2023 QSR
Effects of Reinsurance [Line Items]
Quota Share %	15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	62.00%
Optional Reduced Quota Shares %, option 1	12.50%
Optional Reduced Quota Shares %, option 2	10.00%
2023 QSR
Effects of Reinsurance [Line Items]
Quota Share %	10.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	58.50%
Optional Reduced Quota Shares %, option 1	8.00%
Optional Reduced Quota Shares %, option 2	7.00%
2024 QSR
Effects of Reinsurance [Line Items]
Quota Share %	30.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	56.00%
Optional Reduced Quota Shares %, option 1	23.00%
Optional Reduced Quota Shares %, option 2	15.00%
2025 QSR
Effects of Reinsurance [Line Items]
Quota Share %	40.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	63.00%
Optional Reduced Quota Shares %, option 1	30.00%
Optional Reduced Quota Shares %, option 2	20.00%
2026 QSR
Effects of Reinsurance [Line Items]
Quota Share %	40.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	62.00%
Optional Reduced Quota Shares %, option 1	30.00%
Optional Reduced Quota Shares %, option 2	20.00%
Credit Union QSR \| New Insurance Written In 2020 through 2025
Effects of Reinsurance [Line Items]
Quota Share %	65.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	50.00%
Credit Union QSR \| New Insurance Written In 2026 through 2030
Effects of Reinsurance [Line Items]
Quota Share %	65.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent)	60.00%

Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option One

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Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option Two

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