Loans - Schedule of Allowance for Loan Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 14,020	$ 13,417	$ 13,964	$ 13,976
Charge-offs	(134)	(611)	(266)	(1,437)
Recoveries	46	17	84	34
Provisions	125	320	275	570
Allowance for Loan Losses, Ending Balance	14,057	13,143	14,057	13,143
Allowance for Loan Losses, Ending Balance	14,020	13,417	13,964	13,976	$ 14,057	$ 13,964	$ 13,143
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					14,057	13,964	13,143
Total Loans Receivable					1,279,264	1,302,465	1,246,798
Loans receivables: Ending balance: individually evaluated for impairment					6,397	7,300	7,343
Loans Receivable: Ending balance: collectively evaluated for impairment					1,272,867	1,295,165	1,239,455
Commercial and Industrial
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,620	2,974	2,597	3,219
Charge-offs	(71)	(489)	(102)	(878)
Recoveries	7	4	21	11
Provisions	(94)	(56)	(54)	81
Allowance for Loan Losses, Ending Balance	2,462	2,433	2,462	2,433
Allowance for Loan Losses, Ending Balance	2,620	2,974	2,597	3,219	2,462	2,597	2,433
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					2,462	2,597	2,433
Total Loans Receivable					161,379	174,182	160,674
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					161,379	174,182	160,674
Commercial Real Estate
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	6,278	5,455	6,208	5,228
Charge-offs	0	0	0	(33)
Recoveries	0	0	0	0
Provisions	134	266	204	526
Allowance for Loan Losses, Ending Balance	6,412	5,721	6,412	5,721
Allowance for Loan Losses, Ending Balance	6,278	5,455	6,208	5,228	6,412	6,208	5,721
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					6,412	6,208	5,721
Total Loans Receivable					552,731	548,923	514,519
Loans receivables: Ending balance: individually evaluated for impairment					5,747	6,763	7,242
Loans Receivable: Ending balance: collectively evaluated for impairment					546,984	542,160	507,277
Commercial Real Estate Construction
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	241	135	203	126
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	21	11	59	20
Allowance for Loan Losses, Ending Balance	262	146	262	146
Allowance for Loan Losses, Ending Balance	241	135	203	126	262	203	146
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					262	203	146
Total Loans Receivable					20,428	20,298	19,615
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					20,428	20,298	19,615
Residential Mortgage
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,737	2,936	2,814	3,226
Charge-offs	0	(106)	(6)	(489)
Recoveries	0	12	1	22
Provisions	9	(2)	(63)	81
Allowance for Loan Losses, Ending Balance	2,746	2,840	2,746	2,840
Allowance for Loan Losses, Ending Balance	2,737	2,936	2,814	3,226	2,746	2,814	2,840
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					2,746	2,814	2,840
Total Loans Receivable					419,940	434,299	431,049
Loans receivables: Ending balance: individually evaluated for impairment					650	537	101
Loans Receivable: Ending balance: collectively evaluated for impairment					419,290	433,762	430,948
Home Equity Lines of Credit
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	616	593	611	612
Charge-offs	0	0	(51)	0
Recoveries	8	0	8	0
Provisions	1	(29)	57	(48)
Allowance for Loan Losses, Ending Balance	625	564	625	564
Allowance for Loan Losses, Ending Balance	616	593	611	612	625	611	564
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					625	611	564
Total Loans Receivable					110,585	110,363	106,089
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					110,585	110,363	106,089
Consumer
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	697	725	692	749
Charge-offs	(63)	(16)	(107)	(37)
Recoveries	31	1	54	1
Provisions	23	(37)	49	(40)
Allowance for Loan Losses, Ending Balance	688	673	688	673
Allowance for Loan Losses, Ending Balance	697	725	692	749	688	692	673
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					688	692	673
Total Loans Receivable					14,201	14,400	14,852
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					14,201	14,400	14,852
Unallocated
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	831	599	839	816
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	31	167	23	(50)
Allowance for Loan Losses, Ending Balance	862	766	862	766
Allowance for Loan Losses, Ending Balance	$ 831	$ 599	$ 839	$ 816	862	839	766
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					862	839	766
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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