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Investments - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Net Investment Income [Line Items] |  |
Investment grade rating | 95.20% |
FHLB funding agreements | $ 792.5 | $ 787.5
Investment Grade |  |
Net Investment Income [Line Items] |  |
Increase in credit spread (percent) | 0.40% |
Decrease in total returns (percent) | 15.40% |
Increase to Bloomberg Barclays Index Yield-To-Worst (percent) | 3.10% |
Bloomberg Barclays Index Yield-to-Worst | 5.40% |
High Yield Index |  |
Net Investment Income [Line Items] |  |
Increase in credit spread (percent) | 1.71% |
Decrease in total returns (percent) | 11.20% |
Increase to Bloomberg Barclays Index Yield-To-Worst (percent) | 4.80% |
Bloomberg Barclays Index Yield-to-Worst | 9.00% |
Ten Year United States Treasury |  |
Net Investment Income [Line Items] |  |
Increase in interest rates | 2.36% |
Federal interest rate on securities (percent) | 3.87% | 1.51%
FHLB of Chicago |  |
Net Investment Income [Line Items] |  |
Fair Value | $ 860.4 | $ 870.1
Governmental agencies as required by law in various states |  |
Net Investment Income [Line Items] |  |
Fair Value | $ 28.6 | $ 26.2

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