Allowance for Loan Losses - Composition of Allowance for Loans Losses, by Class (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	$ 462	$ 2,213	$ 2,308
Allowance for Loans Evaluated Collectively for Impairment	15,791	9,426	8,924
Total Allowance for Loan Losses	16,253	11,639	11,232	$ 10,729
Commercial \| Real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	112	251	260
Allowance for Loans Evaluated Collectively for Impairment	5,066	3,491	3,307
Total Allowance for Loan Losses	5,178	3,742	3,567	3,872
Commercial \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	18	0	0
Allowance for Loans Evaluated Collectively for Impairment	644	365	255
Total Allowance for Loan Losses	662	365	255	434
Commercial \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	169	1,273	1,696
Allowance for Loans Evaluated Collectively for Impairment	3,269	2,056	1,845
Total Allowance for Loan Losses	3,438	3,329	3,541	3,358
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	171	27	24
Total Allowance for Loan Losses	171	27	24	20
Residential \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	102	25	34
Total Allowance for Loan Losses	102	25	34	36
Residential \| Term
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	163	237	335
Allowance for Loans Evaluated Collectively for Impairment	2,416	787	900
Total Allowance for Loan Losses	2,579	1,024	1,235	1,130
Home equity line of credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	447	17
Allowance for Loans Evaluated Collectively for Impairment	1,211	631	713
Total Allowance for Loan Losses	1,211	1,078	730	692
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	5	0
Allowance for Loans Evaluated Collectively for Impairment	778	862	630
Total Allowance for Loan Losses	778	867	630	545
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	2,134	1,182	1,216
Total Allowance for Loan Losses	$ 2,134	$ 1,182	$ 1,216	$ 642

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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