Investments (Investments Pledged as Collateral) (Details) $ in Millions	Dec. 31, 2023 USD ($)
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

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.

No definition available.

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Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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