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Investments Federal Home Loan Bank Carrying Amount, Collateral Posted and Advances Received (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
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Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank Common Stock | $ 15.7 | $ 17.1
Federal Home Loan Bank, Advances | 68.0 | 99.1
Federal Home Loan Bank, Collateral Posted to FHLB | 1,204.1 | 1,329.0
Fixed Maturity Securities |  |
Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank, Collateral Posted to FHLB | 420.2 | 527.1
Commercial Mortgage Loans |  |
Federal Home Loan Bank Carrying Value of Common Stock, Collateral Posted and Advances |  |
Federal Home Loan Bank, Collateral Posted to FHLB | $ 783.9 | $ 801.9

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- Definition Amount of advances from the Federal Home Loan Bank (FHLB). + 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//1943274/2147480876/942-470-45-1 + 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//1943274/2147480876/942-470-45-1 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//1943274/2147480848/942-470-50-3 + 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://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 325 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481026/942-325-45-1 + Details
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