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v3.23.1

Investments - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Schedule of Investments [Line Items] |  |  |
Investment grade rating | 96.30% |  |
Reverse repurchase agreement, cash to value percentage | 95.00% |  |
Securities sold under agreements to repurchase | $ 70.2 | $ 70.2 |
Fair Value | 5,350.0 | 5,185.0 |
FHLB funding agreements | 869.5 | 792.5 |
Fair Value |  |  |
Schedule of Investments [Line Items] |  |  |
Securities sold under agreements to repurchase | 74.7 | 73.3 |
FHLB of Chicago |  |  |
Schedule of Investments [Line Items] |  |  |
Fair Value | 948.1 | 860.4 |
Governmental Agencies as Required by Law in Various States |  |  |
Schedule of Investments [Line Items] |  |  |
Fair Value | $ 29.0 | $ 28.6 |
Investment Grade |  |  |
Schedule of Investments [Line Items] |  |  |
Increase in credit spread (percent) | 0.46% |  |
Decrease in total returns (percent) | 12.80% |  |
Increase to Bloomberg Barclays Index Yield-To-Worst (percent) | 2.84% |  |
Bloomberg Barclays Index Yield-to-Worst | 5.20% |  |
High Yield |  |  |
Schedule of Investments [Line Items] |  |  |
Increase in credit spread (percent) | 1.72% |  |
Decrease in total returns (percent) | 8.00% |  |
Increase to Bloomberg Barclays Index Yield-To-Worst (percent) | 4.31% |  |
Bloomberg Barclays Index Yield-to-Worst | 8.50% |  |
10-year U.S. Treasury |  |  |
Schedule of Investments [Line Items] |  |  |
Increase in interest rates | 1.96% |  |
Federal interest rate on securities (percent) | 3.47% |  | 1.51%

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