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Investments - Schedule of Investments Pledged as Collateral (Details) $ in Millions | Mar. 31, 2025 USD ($)
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Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | $ 24.9
Securities owned and pledged as collateral, fair value | 118.8
U.S. government and government agencies |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 23.1
Securities owned and pledged as collateral, fair value | 23.1
Obligations of states and political subdivisions |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 1.8
Securities owned and pledged as collateral, fair value | 1.8
RMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 0.0
Securities owned and pledged as collateral, fair value | 85.7
CMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 0.0
Securities owned and pledged as collateral, fair value | 8.2
Federal Home Loan Bank of Indianapolis |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 64.7
Federal Home Loan Bank of Indianapolis | U.S. government and government agencies |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of Indianapolis | Obligations of states and political subdivisions |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of Indianapolis | RMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 64.2
Federal Home Loan Bank of Indianapolis | CMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 0.5
Federal Home Loan Bank of New York |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 29.2
Federal Home Loan Bank of New York | U.S. government and government agencies |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of New York | Obligations of states and political subdivisions |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of New York | RMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | 21.5
Federal Home Loan Bank of New York | CMBS |
Financial Instruments Owned and Pledged as Collateral [Line Items] |
Securities pledged as collateral with FHLB | $ 7.7

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- Definition Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. + References No definition available. + Details
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- Definition Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 825 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147477351/944-825-50-1A + 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(11)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481444/860-30-45-1 + Details
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