Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Allowance for Loan Losses [Roll Forward]
Beginning balance		$ 5,227	$ 5,176	$ 5,176
Charge-offs		(177)	(129)	(391)
Recoveries		45	93	96
Provision (recovery)	$ 345	1,606	255	346
Ending balance	6,701	6,701	5,395	5,227
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	80	80		229
Ending balances collectively evaluated for impairment	6,621	6,621		4,998
Loans receivable, individually evaluated for impairment	9,255	9,255		3,646
Loans receivable, collectively evaluated for impairment	628,848	628,848		546,580
Total Loans	638,103	638,103		550,226
Commercial and Industrial [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		296	483	483
Charge-offs		(148)	(93)	(328)
Recoveries		11	2	2
Provision (recovery)		699	162	139
Ending balance	858	858	554	296
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	20	20		0
Ending balances collectively evaluated for impairment	838	838		296
Loans receivable, individually evaluated for impairment	509	509		187
Loans receivable, collectively evaluated for impairment	88,473	88,473		27,217
Total Loans	88,982	88,982		27,404
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		1,788	1,738	1,738
Charge-offs		0	0	0
Recoveries		14	77	80
Provision (recovery)		361	(34)	(30)
Ending balance	2,163	2,163	1,781	1,788
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	60	60		229
Ending balances collectively evaluated for impairment	2,103	2,103		1,559
Loans receivable, individually evaluated for impairment	8,369	8,369		2,847
Loans receivable, collectively evaluated for impairment	191,404	191,404		179,051
Total Loans	199,773	199,773		181,898
Construction and Land [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		652	635	635
Charge-offs		0	0	0
Recoveries		0	0	0
Provision (recovery)		294	15	17
Ending balance	946	946	650	652
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	946	946		652
Loans receivable, individually evaluated for impairment	0	0		233
Loans receivable, collectively evaluated for impairment	72,465	72,465		64,998
Total Loans	72,465	72,465		65,231
Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		154	145	145
Charge-offs		(21)	(24)	(50)
Recoveries		20	14	14
Provision (recovery)		(18)	10	45
Ending balance	135	135	145	154
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	135	135		154
Loans receivable, individually evaluated for impairment	0	0		0
Loans receivable, collectively evaluated for impairment	6,264	6,264		5,958
Total Loans	6,264	6,264		5,958
Student [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		65	68	68
Charge-offs		(8)	(12)	(13)
Recoveries		0	0	0
Provision (recovery)		31	9	10
Ending balance	88	88	65	65
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	88	88		65
Loans receivable, individually evaluated for impairment	0	0		0
Loans receivable, collectively evaluated for impairment	7,333	7,333		8,151
Total Loans	7,333	7,333		8,151
Residential Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		1,596	1,311	1,311
Charge-offs		0	0	0
Recoveries		0	0	0
Provision (recovery)		263	137	285
Ending balance	1,859	1,859	1,448	1,596
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	1,859	1,859		1,596
Loans receivable, individually evaluated for impairment	377	377		379
Loans receivable, collectively evaluated for impairment	232,147	232,147		224,937
Total Loans	232,524	232,524		225,316
Home Equity Lines of Credit [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance		326	446	446
Charge-offs		0	0	0
Recoveries		0	0	0
Provision (recovery)		(24)	(44)	(120)
Ending balance	302	302	402	326
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	302	302		326
Loans receivable, individually evaluated for impairment	0	0		0
Loans receivable, collectively evaluated for impairment	30,762	30,762		36,268
Total Loans	30,762	30,762		36,268
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	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 valuation allowance for financing receivables that are expected to be uncollectible that were individually 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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