Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Allowance for loan losses:
Beginning Balance	$ 4,542	$ 4,015	$ 5,113	$ 2,231
Provision (credit) charged to expense	(400)	1,333	(855)	3,304
Losses charged off	(31)	(144)	(173)	(385)
Recoveries	12	24	38	78
Ending Balance	4,123	5,228	4,123	5,228
Allocation:
Ending balance: individually evaluated for impairment	85	25	85	25	$ 1
Ending balance: collectively evaluated for impairment	4,038	5,203	4,038	5,203	5,112
Loans:
Ending balance: individually evaluated for impairment	2,640	1,295	2,640	1,295	376
Ending balance: collectively evaluated for impairment	459,479	441,981	459,479	441,981	443,115
Commercial
Allowance for loan losses:
Beginning Balance	1,140	2,344	1,397	568
Provision (credit) charged to expense	(249)	(1,031)	(428)	777
Losses charged off		(5)	(78)	(47)
Recoveries	3	13	3	23
Ending Balance	894	1,321	894	1,321
Allocation:
Ending balance: individually evaluated for impairment		4		4
Ending balance: collectively evaluated for impairment	894	1,317	894	1,317	1,397
Loans:
Ending balance: individually evaluated for impairment		22		22	80
Ending balance: collectively evaluated for impairment	99,880	100,438	99,880	100,438	103,197
Commercial Real Estate
Allowance for loan losses:
Beginning Balance	1,710	751	1,821	792
Provision (credit) charged to expense	(155)	1,202	(266)	1,288
Losses charged off		(63)		(190)
Ending Balance	1,555	1,890	1,555	1,890
Allocation:
Ending balance: individually evaluated for impairment	85	21	85	21	1
Ending balance: collectively evaluated for impairment	1,470	1,869	1,470	1,869	1,820
Loans:
Ending balance: individually evaluated for impairment	2,640	614	2,640	614	182
Ending balance: collectively evaluated for impairment	263,383	244,729	263,383	244,729	245,985
Residential
Allowance for loan losses:
Beginning Balance	1,353	600	1,471	572
Provision (credit) charged to expense	(34)	988	(133)	1,027
Losses charged off		(21)	(26)	(33)
Recoveries		1	7	2
Ending Balance	1,319	1,568	1,319	1,568
Allocation:
Ending balance: collectively evaluated for impairment	1,319	1,568	1,319	1,568	1,471
Loans:
Ending balance: individually evaluated for impairment		525		525	114
Ending balance: collectively evaluated for impairment	89,280	88,093	89,280	88,093	85,675
Installment
Allowance for loan losses:
Beginning Balance	339	320	424	299
Provision (credit) charged to expense	38	174	(28)	212
Losses charged off	(31)	(55)	(69)	(115)
Recoveries	9	10	28	53
Ending Balance	355	449	355	449
Allocation:
Ending balance: collectively evaluated for impairment	355	449	355	449	424
Loans:
Ending balance: individually evaluated for impairment		134		134
Ending balance: collectively evaluated for impairment	$ 6,936	$ 8,721	$ 6,936	$ 8,721	$ 8,258

Financing Receivable Additional Information [Abstract]

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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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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