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Investments (Investments Pledged as Collateral) (Details) $ in Millions | Dec. 31, 2023 USD ($)
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U.S. Government and Government Agencies [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | $ 19.9
Securities owned and pledged as collateral, fair value | 19.9
Obligations of States and Political Subdivisions [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 3.5
Securities owned and pledged as collateral, fair value | 3.5
Residential Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 0.0
Securities owned and pledged as collateral, fair value | 94.5
Commercial Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 0.0
Securities owned and pledged as collateral, fair value | 11.1
Available-for-sale Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral on deposit with various state and regulatory agencies | 23.4
Securities owned and pledged as collateral, fair value | 129.0
Federal Home Loan Bank of New York [Member] | U.S. Government and Government Agencies [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of New York [Member] | Obligations of States and Political Subdivisions [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of New York [Member] | Residential Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 25.3
Federal Home Loan Bank of New York [Member] | Commercial Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 8.6
Federal Home Loan Bank of New York [Member] | Available-for-sale Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 33.9
Federal Home Loan Bank of Indianapolis [Member] | U.S. Government and Government Agencies [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of Indianapolis [Member] | Obligations of States and Political Subdivisions [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 0.0
Federal Home Loan Bank of Indianapolis [Member] | Residential Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 69.2
Federal Home Loan Bank of Indianapolis [Member] | Commercial Mortgage Backed Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | 2.5
Federal Home Loan Bank of Indianapolis [Member] | Available-for-sale Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Securities pledged as collateral with FHLB | $ 71.7

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