Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan Losses [Roll Forward]
Beginning balance	$ 5,176	$ 5,094	$ 4,525
Charge-offs	(391)	(783)	(691)
Recoveries	96	358	740
Provision (recovery)	346	507	520
Ending balance	5,227	5,176	5,094
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	229	403	912
Ending balances collectively evaluated for impairment	4,998	4,773	4,182
Loans receivable, individually evaluated for impairment	3,646	7,666	10,862
Loans receivable, collectively evaluated for impairment	546,580	541,698	491,937
Total Loans	550,226	549,364	502,799
Commercial and Industrial [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	483	518	561
Charge-offs	(328)	(106)	(19)
Recoveries	2	35	154
Provision (recovery)	139	36	(178)
Ending balance	296	483	518
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	176	247
Ending balances collectively evaluated for impairment	296	307	271
Loans receivable, individually evaluated for impairment	187	522	758
Loans receivable, collectively evaluated for impairment	27,217	26,199	23,655
Total Loans	27,404	26,721	24,413
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,738	1,609	1,569
Charge-offs	0	(47)	(476)
Recoveries	80	70	575
Provision (recovery)	(30)	106	(59)
Ending balance	1,788	1,738	1,609
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	229	159	257
Ending balances collectively evaluated for impairment	1,559	1,579	1,352
Loans receivable, individually evaluated for impairment	2,847	3,191	3,631
Loans receivable, collectively evaluated for impairment	179,051	184,606	173,196
Total Loans	181,898	187,797	176,827
Construction and Land [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	635	879	661
Charge-offs	0	(312)	0
Recoveries	0	0	0
Provision (recovery)	17	68	218
Ending balance	652	635	879
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	357
Ending balances collectively evaluated for impairment	652	635	522
Loans receivable, individually evaluated for impairment	233	2,679	5,234
Loans receivable, collectively evaluated for impairment	64,998	68,730	48,928
Total Loans	65,231	71,409	54,162
Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	145	105	21
Charge-offs	(50)	(14)	(114)
Recoveries	14	4	2
Provision (recovery)	45	50	196
Ending balance	154	145	105
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	154	145	105
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	5,958	5,562	5,068
Total Loans	5,958	5,562	5,068
Student [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	68	72	76
Charge-offs	(13)	(24)	(31)
Recoveries	0	0	0
Provision (recovery)	10	20	27
Ending balance	65	68	72
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	65	68	72
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	8,151	9,158	10,677
Total Loans	8,151	9,158	10,677
Residential Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,311	1,174	943
Charge-offs	0	(200)	(51)
Recoveries	0	248	6
Provision (recovery)	285	89	276
Ending balance	1,596	1,311	1,174
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	1,596	1,311	1,174
Loans receivable, individually evaluated for impairment	379	707	581
Loans receivable, collectively evaluated for impairment	224,937	205,238	186,523
Total Loans	225,316	205,945	187,104
Home Equity Lines of Credit [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	446	387	307
Charge-offs	0	(80)	0
Recoveries	0	1	3
Provision (recovery)	(120)	138	77
Ending balance	326	446	387
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	68	51
Ending balances collectively evaluated for impairment	326	378	336
Loans receivable, individually evaluated for impairment	0	567	658
Loans receivable, collectively evaluated for impairment	36,268	42,205	43,890
Total Loans	36,268	42,772	44,548
Unallocated [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	350	350	387
Charge-offs	0	0	0
Recoveries	0	0	0
Provision (recovery)	0	0	(37)
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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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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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The balance of financing receivables 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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Amount of expense related to estimated loss from loan and lease transactions.

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