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Investments Federal Home Loan Bank Carrying Amount, Collateral Posted and Advances Received (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank Common Stock | $ 38.0 | $ 26.7
Federal Home Loan Bank, Advances | 585.4 | 324.2
Federal Home Loan Bank, Collateral Posted to FHLB | 1,879.6 | 1,461.8
Fixed Maturity Securities |  |
Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank, Collateral Posted to FHLB | 754.9 | 553.6
Commercial Mortgage Loans |  |
Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank, Collateral Posted to FHLB | $ 1,124.7 | $ 908.2

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- Definition Amount of advance from Federal Home Loan Bank (FHLBank). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 + Details
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- Definition Amount of the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 325 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477974/942-325-45-1 + Details
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