Borrowings (Schedule of Advances to the Federal Home Loan Bank) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
FHLBB borrowings	$ 25,000
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Two		$ 10,000
FHLB advances, carrying value of residential real estate and commercial loans pledged as collateral	1,400,000	1,100,000
FHLB advances, securities pledged as collateral	150	172
Federal Home Loan Bank Advances	$ 40,825	$ 35,000
Long-term Debt [Member]
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Debt, Weighted Average Interest Rate	1.87%	2.19%
Short-term Debt
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Debt, Weighted Average Interest Rate	1.28%	1.43%
FHLBB borrowings
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Debt, Weighted Average Interest Rate	1.87%	1.87%
FHLBB borrowings \| Long-term Debt [Member]
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Debt, Weighted Average Interest Rate	1.87%	1.87%
FHLBB borrowings \| Long-term Debt [Member]
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Long-term Federal Home Loan Bank Advances	$ 10,000	$ 10,000
FHLBB borrowings \| Short-term Debt
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
FHLBB borrowings	$ 25,000	$ 25,000
Debt, Weighted Average Interest Rate	1.79%	2.71%
FHLBB Borrowing Maturing February 2020
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Federal Home Loan Bank Advances	$ 10,000
FHLBB Borrowing Maturing January 2020
Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]
Federal Home Loan Bank Advances	$ 30,825

Maturity Schedule Of Federal Home Loan Bank Advances [Line Items]

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Weighted average interest rate of debt outstanding.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for FHLB debt obligations, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

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