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v3.25.3

Investments - Narrative (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Schedule of Investments [Line Items] |  |
Investment grade rating | 97.80% |
Reverse repurchase agreement, cash to value percentage | 95.00% |
Securities sold under agreements to repurchase | $ 0.0 | $ 12.0
Fair Value | 5,666.5 | 5,387.9
FHLB funding agreements | 1,039.5 | 989.5
FHLB of Chicago |  |
Schedule of Investments [Line Items] |  |
Fair Value | 1,109.5 | 1,072.2
Governmental Agencies as Required by Law in Various States |  |
Schedule of Investments [Line Items] |  |
Fair Value | 25.9 | 27.1
Fair Value |  |
Schedule of Investments [Line Items] |  |
Securities sold under agreements to repurchase | $ 0.0 | $ 12.4

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