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, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 18,353	$ 14,057	$ 13,835	$ 13,964
Charge-offs	(752)	(299)	(2,876)	(565)
Recoveries	49	16	141	100
Provisions (credits)	1,550	150	8,100	425
Allowance for Loan Losses, Ending Balance	19,200	13,924	19,200	13,924
Allowance for Loan Losses, Ending Balance	19,200	13,924	13,835	13,964	$ 19,200	$ 13,835	$ 13,924
Allowance for loan losses: Ending balance: individually evaluated for impairment					236	42	48
Allowance for loan losses: Ending balance: collectively evaluated for impairment					18,964	13,793	13,876
Total Loans Receivable					1,700,883	1,272,601	1,288,285
Loans receivables: Ending balance: individually evaluated for impairment					10,592	7,702	6,955
Loans Receivable: Ending balance: collectively evaluated for impairment					1,690,291	1,264,899	1,281,330
Commercial and Industrial
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,656	2,462	2,400	2,597
Charge-offs	(14)	(28)	(2,048)	(130)
Recoveries	3	4	78	25
Provisions (credits)	430	88	2,645	34
Allowance for Loan Losses, Ending Balance	3,075	2,526	3,075	2,526
Allowance for Loan Losses, Ending Balance	3,075	2,526	2,400	2,597	3,075	2,400	2,526
Allowance for loan losses: Ending balance: individually evaluated for impairment					23	42	48
Allowance for loan losses: Ending balance: collectively evaluated for impairment					3,052	2,358	2,478
Total Loans Receivable					345,011	149,315	163,718
Loans receivables: Ending balance: individually evaluated for impairment					46	65	72
Loans Receivable: Ending balance: collectively evaluated for impairment					344,965	149,250	163,646
Commercial Real Estate
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	8,135	6,412	6,693	6,208
Charge-offs	(675)	0	(675)	0
Recoveries	0	5	6	5
Provisions (credits)	2,272	(4)	3,708	200
Allowance for Loan Losses, Ending Balance	9,732	6,413	9,732	6,413
Allowance for Loan Losses, Ending Balance	9,732	6,413	6,693	6,208	9,732	6,693	6,413
Allowance for loan losses: Ending balance: individually evaluated for impairment					213	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					9,519	6,693	6,413
Total Loans Receivable					754,074	567,048	557,655
Loans receivables: Ending balance: individually evaluated for impairment					10,445	7,383	6,578
Loans Receivable: Ending balance: collectively evaluated for impairment					743,629	559,665	551,077
Commercial Real Estate Construction
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	251	262	298	203
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (credits)	222	89	175	148
Allowance for Loan Losses, Ending Balance	473	351	473	351
Allowance for Loan Losses, Ending Balance	473	351	298	351	473	298	351
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					473	298	351
Total Loans Receivable					50,367	26,416	28,061
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					50,367	26,416	28,061
Residential Mortgage
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	3,074	2,746	2,555	2,814
Charge-offs	0	(36)	0	(42)
Recoveries	0	0	0	1
Provisions (credits)	504	(69)	1,023	(132)
Allowance for Loan Losses, Ending Balance	3,578	2,641	3,578	2,641
Allowance for Loan Losses, Ending Balance	3,578	2,641	2,555	2,814	3,578	2,555	2,641
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					3,578	2,555	2,641
Total Loans Receivable					428,480	408,337	415,277
Loans receivables: Ending balance: individually evaluated for impairment					101	171	212
Loans Receivable: Ending balance: collectively evaluated for impairment					428,379	408,166	415,065
Home Equity Lines of Credit
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	661	625	619	611
Charge-offs	0	(174)	0	(225)
Recoveries	28	0	29	8
Provisions (credits)	58	159	99	216
Allowance for Loan Losses, Ending Balance	747	610	747	610
Allowance for Loan Losses, Ending Balance	747	610	619	610	747	619	610
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					747	619	610
Total Loans Receivable					109,293	108,047	109,630
Loans receivables: Ending balance: individually evaluated for impairment					0	83	93
Loans Receivable: Ending balance: collectively evaluated for impairment					109,293	107,964	109,537
Consumer
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	661	688	650	692
Charge-offs	(63)	(61)	(153)	(168)
Recoveries	18	7	28	61
Provisions (credits)	134	20	225	69
Allowance for Loan Losses, Ending Balance	750	654	750	654
Allowance for Loan Losses, Ending Balance	750	654	650	654	750	650	654
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					750	650	654
Total Loans Receivable					13,658	13,438	13,944
Loans receivables: Ending balance: individually evaluated for impairment					0	0	0
Loans Receivable: Ending balance: collectively evaluated for impairment					13,658	13,438	13,944
Unallocated
Allowance for Loan Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,915	862	620	839
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (credits)	(2,070)	(133)	225	(110)
Allowance for Loan Losses, Ending Balance	845	729	845	729
Allowance for Loan Losses, Ending Balance	$ 845	$ 729	$ 620	$ 839	845	620	729
Allowance for loan losses: Ending balance: individually evaluated for impairment					0	0	0
Allowance for loan losses: Ending balance: collectively evaluated for impairment					845	620	729
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 increase in allowance for credit loss on financing receivable from recovery.

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

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- Definition

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 credit loss expense (reversal of expense) for financing receivable.

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