Fair Value Measurements (Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments, Held or Issued for Purposes Other Than Trading) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financial assets:
Cash and cash equivalents	$ 83,819	$ 59,658	$ 28,613
Debt securities available-for-sale	32,215	41,790
Federal Home Loan Bank of Boston stock	895	1,416
Loans, net	1,314,810	959,286
Accrued interest receivable	6,371	2,854
Financial liabilities:
Deposits	1,237,428	849,905
Borrowings	13,500	24,998
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	83,819	59,658
Debt securities available-for-sale	32,215	41,790
Federal Home Loan Bank of Boston stock	895	1,416
Loans, net	1,314,810	959,286
Accrued interest receivable	6,371	2,854
Financial liabilities:
Deposits	1,237,428	849,905
Borrowings	13,500	24,998
Fair Value [Member]
Financial assets:
Cash and cash equivalents	83,819	59,658
Debt securities available-for-sale	32,215	41,790
Loans, net	1,321,143	958,270
Accrued interest receivable	6,371	2,854
Financial liabilities:
Deposits	1,237,867	850,774
Borrowings	14,016	25,351
Quoted Prices In Active Markets Identical Assets Level 1 [Member] \| Fair Value [Member]
Financial assets:
Cash and cash equivalents	83,819	59,658
Significant Other Observable Inputs Level 2 [Member] \| Fair Value [Member]
Financial assets:
Debt securities available-for-sale	32,215	41,790
Accrued interest receivable	6,371	2,854
Financial liabilities:
Deposits	1,237,867	850,774
Borrowings	14,016	25,351
Significant Unobservable Inputs Level 3 [Member] \| Fair Value [Member]
Financial assets:
Loans, net	$ 1,321,143	$ 958,270

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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