Loans - Schedule of Allowance for Loan Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 14,057	$ 13,143	$ 13,964	$ 13,976
Charge-offs	(299)	(62)	(565)	(1,499)
Recoveries	16	133	100	167
Provisions	150	200	425	770
Allowance for Loan Losses, Ending Balance	13,924	13,414	13,924	13,414
Allowance for Loan Losses, Ending Balance	14,057	13,143	13,964	13,976	$ 13,924	$ 13,964	$ 13,414
Allowance for loan losses: Ending balance: individually evaluated for impairment					48	0	148
Allowance for loan losses: Ending balance: collectively evaluated for impairment					13,876	13,964	13,266
Total Loans Receivable					1,288,285	1,302,465	1,272,446
Loans receivables: Ending balance: individually evaluated for impairment					6,955	7,300	7,869
Loans Receivable: Ending balance: collectively evaluated for impairment					1,281,330	1,295,165	1,264,577
Commercial and Industrial
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,462	2,433	2,597	3,219
Charge-offs	(28)	(33)	(130)	(911)
Recoveries	4	22	25	33
Provisions	88	185	34	266
Allowance for Loan Losses, Ending Balance	2,526	2,607	2,526	2,607
Allowance for Loan Losses, Ending Balance	2,462	2,433	2,597	3,219	2,526	2,597	2,607
Allowance for loan losses: Ending balance: individually evaluated for impairment					48	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					2,478	2,597	2,607
Total Loans Receivable					163,718	174,182	176,073
Loans receivables: Ending balance: individually evaluated for impairment					72	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					163,646	174,182	176,073
Commercial Real Estate
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	6,412	5,721	6,208	5,228
Charge-offs	0	0	0	(33)
Recoveries	5	0	5	0
Provisions	(4)	123	200	649
Allowance for Loan Losses, Ending Balance	6,413	5,844	6,413	5,844
Allowance for Loan Losses, Ending Balance	6,412	5,721	6,208	5,228	6,413	6,208	5,844
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					6,413	6,208	5,844
Total Loans Receivable					557,655	548,923	522,834
Loans receivables: Ending balance: individually evaluated for impairment					6,578	6,763	7,188
Loans Receivable: Ending balance: collectively evaluated for impairment					551,077	542,160	515,646
Commercial Real Estate Construction
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	262	146	203	126
Charge-offs	0	0	0	0
Recoveries	0	103	0	103
Provisions	89	(50)	148	(30)
Allowance for Loan Losses, Ending Balance	351	199	351	199
Allowance for Loan Losses, Ending Balance	262	146	203	126	351	203	199
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					351	203	199
Total Loans Receivable					28,061	20,298	18,720
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					28,061	20,298	18,720
Residential Mortgage
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,746	2,840	2,814	3,226
Charge-offs	(36)	0	(42)	(489)
Recoveries	0	8	1	30
Provisions	(69)	(95)	(132)	(14)
Allowance for Loan Losses, Ending Balance	2,641	2,753	2,641	2,753
Allowance for Loan Losses, Ending Balance	2,746	2,840	2,814	3,226	2,641	2,814	2,753
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					2,641	2,814	2,753
Total Loans Receivable					415,277	434,299	433,535
Loans receivables: Ending balance: individually evaluated for impairment					212	537	533
Loans Receivable: Ending balance: collectively evaluated for impairment					415,065	433,762	433,002
Home Equity Lines of Credit
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	625	564	611	612
Charge-offs	(174)	0	(225)	0
Recoveries	0	0	8	0
Provisions	159	131	216	83
Allowance for Loan Losses, Ending Balance	610	695	610	695
Allowance for Loan Losses, Ending Balance	625	564	611	612	610	611	695
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	148
Allowance for loan losses: Ending balance: collectively evaluated for impairment					610	611	547
Total Loans Receivable					109,630	110,363	106,679
Loans receivables: Ending balance: individually evaluated for impairment					93	0	148
Loans Receivable: Ending balance: collectively evaluated for impairment					109,537	110,363	106,531
Consumer
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	688	673	692	749
Charge-offs	(61)	(29)	(168)	(66)
Recoveries	7	0	61	1
Provisions	20	(9)	69	(49)
Allowance for Loan Losses, Ending Balance	654	635	654	635
Allowance for Loan Losses, Ending Balance	688	673	692	749	654	692	635
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					654	692	635
Total Loans Receivable					13,944	14,400	14,605
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					13,944	14,400	14,605
Unallocated
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	862	766	839	816
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	(133)	(85)	(110)	(135)
Allowance for Loan Losses, Ending Balance	729	681	729	681
Allowance for Loan Losses, Ending Balance	$ 862	$ 766	$ 839	$ 816	729	839	681
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					729	839	681
Total Loans Receivable					0	0	0
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					$ 0	$ 0	$ 0

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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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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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 writeoff of financing receivable, charged against allowance for credit loss.

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The balance of financing receivables that were collectively evaluated for impairment.

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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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