Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan Losses [Roll Forward]
Beginning balance	$ 5,227	$ 5,176	$ 5,094
Charge-offs	(197)	(391)	(783)
Recoveries	67	96	358
Provision (recovery)	1,773	346	507
Ending balance	6,870	5,227	5,176
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	72	229	403
Ending balances collectively evaluated for impairment	6,798	4,998	4,773
Loans receivable, individually evaluated for impairment	9,608	3,646	7,666
Loans receivable, collectively evaluated for impairment	607,141	546,580	541,698
Total Loans	616,749	550,226	549,364
Commercial and Industrial [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	296	483	518
Charge-offs	(148)	(328)	(106)
Recoveries	13	2	35
Provision (recovery)	590	139	36
Ending balance	751	296	483
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	20	0	176
Ending balances collectively evaluated for impairment	731	296	307
Loans receivable, individually evaluated for impairment	509	187	522
Loans receivable, collectively evaluated for impairment	67,881	27,217	26,199
Total Loans	68,390	27,404	26,721
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,788	1,738	1,609
Charge-offs	0	0	(47)
Recoveries	24	80	70
Provision (recovery)	522	(30)	106
Ending balance	2,334	1,788	1,738
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	52	229	159
Ending balances collectively evaluated for impairment	2,282	1,559	1,579
Loans receivable, individually evaluated for impairment	8,345	2,847	3,191
Loans receivable, collectively evaluated for impairment	192,345	179,051	184,606
Total Loans	200,690	181,898	187,797
Construction and Land [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	652	635	879
Charge-offs	0	0	(312)
Recoveries	0	0	0
Provision (recovery)	428	17	68
Ending balance	1,080	652	635
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	1,080	652	635
Loans receivable, individually evaluated for impairment	0	233	2,679
Loans receivable, collectively evaluated for impairment	73,966	64,998	68,730
Total Loans	73,966	65,231	71,409
Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	154	145	105
Charge-offs	(34)	(50)	(14)
Recoveries	30	14	4
Provision (recovery)	(24)	45	50
Ending balance	126	154	145
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	126	154	145
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	6,355	5,958	5,562
Total Loans	6,355	5,958	5,562
Student [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	65	68	72
Charge-offs	(15)	(13)	(24)
Recoveries	0	0	0
Provision (recovery)	31	10	20
Ending balance	81	65	68
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	81	65	68
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	6,971	8,151	9,158
Total Loans	6,971	8,151	9,158
Residential Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,596	1,311	1,174
Charge-offs	0	0	(200)
Recoveries	0	0	248
Provision (recovery)	243	285	89
Ending balance	1,839	1,596	1,311
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	1,839	1,596	1,311
Loans receivable, individually evaluated for impairment	754	379	707
Loans receivable, collectively evaluated for impairment	230,131	224,937	205,238
Total Loans	230,885	225,316	205,945
Home Equity Lines of Credit [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	326	446	387
Charge-offs	0	0	(80)
Recoveries	0	0	1
Provision (recovery)	(17)	(120)	138
Ending balance	309	326	446
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	68
Ending balances collectively evaluated for impairment	309	326	378
Loans receivable, individually evaluated for impairment	0	0	567
Loans receivable, collectively evaluated for impairment	29,492	36,268	42,205
Total Loans	29,492	36,268	42,772
Unallocated [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	350	350	350
Charge-offs	0	0	0
Recoveries	0	0	0
Provision (recovery)	0	0	0
Ending balance	350	350	350
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	$ 350	$ 350	$ 350

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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 allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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