Loans (Details 2) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	$ 8,936	$ 6,362	$ 6,627	$ 6,263	$ 6,263
Charge-offs	(25)	(3)	(73)	(112)	(145)
Recoveries	140	209	172	270	370
Provision for loan losses	1,062	25	3,387	139	139
Ending balance December 31, 2019	10,113	6,560	10,113	6,560	6,627
Individually evaluated for impairment	3	14	3	14	6
Collectively evaluated for impairment	10,110	6,546	10,110	6,546	6,621
Ending balance-total	844,460	735,074	844,460	735,074	737,028
Individually evaluated for impairment	3,224	4,155	3,224	4,155	3,997
Collectively evaluated for impairment	841,236	730,919	841,236	730,919	733,031
Commercial, Financial And Agricultural Loan [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	769	435	427	430	430
Charge-offs		(6)		(8)	(12)
Recoveries	118		121		3
Provision for loan losses	(59)	30	280	37	6
Ending balance December 31, 2019	828	459	828	459	427
Individually evaluated for impairment		4		4
Collectively evaluated for impairment	828	455	828	455	427
Ending balance-total	108,006	55,169	108,006	55,169	51,805
Individually evaluated for impairment					400
Collectively evaluated for impairment	108,006	55,165	108,006	55,165	51,405
Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	165	77	111	89	89
Charge-offs	(2)		(2)
Recoveries	2		2
Provision for loan losses	12	14	66	2	22
Ending balance December 31, 2019	177	91	177	91	111
Individually evaluated for impairment
Collectively evaluated for impairment	177	91	177	91	111
Ending balance-total	89,250	58,737	89,250	58,737	73,512
Individually evaluated for impairment
Collectively evaluated for impairment	89,250	58,737	89,250	58,737	73,512
Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	497	404	367	431	431
Charge-offs				(7)	(12)
Recoveries
Provision for loan losses	96	(19)	226	(39)	(52)
Ending balance December 31, 2019	593	385	593	385	367
Individually evaluated for impairment
Collectively evaluated for impairment	593	385	593	385	367
Ending balance-total	49,215	47,693	49,215	47,693	45,357
Individually evaluated for impairment	327	538	327	538	392
Collectively evaluated for impairment	48,888	47,155	48,888	47,155	44,965
Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	6,469	4,458	4,602	4,318	4,318
Charge-offs	(1)		(1)
Recoveries	4	180	13	221	307
Provision for loan losses	982	(102)	2,840	(3)	(23)
Ending balance December 31, 2019	7,454	4,536	7,454	4,536	4,602
Individually evaluated for impairment	3	10	3	10	6
Collectively evaluated for impairment	7,451	4,526	7,451	4,526	4,596
Ending balance-total	561,932	534,554	561,932	534,554	527,447
Individually evaluated for impairment	2,850	3,541	2,850	3,541	3,135
Collectively evaluated for impairment	559,082	531,013	559,082	531,013	524,312
Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	293	247	240	261	261
Charge-offs				(1)	(1)
Recoveries	1	14	2	14	15
Provision for loan losses	36	(20)	88	(33)	(35)
Ending balance December 31, 2019	330	241	330	241	240
Individually evaluated for impairment
Collectively evaluated for impairment	330	241	330	241	240
Ending balance-total	27,618	29,103	27,618	29,103	28,891
Individually evaluated for impairment	47	72	47	72	70
Collectively evaluated for impairment	27,571	29,031	27,571	29,031	28,821
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	132	101	97	88	88
Charge-offs	(22)	(30)	(70)	(96)	(120)
Recoveries	15	15	34	35	45
Provision for loan losses	(2)	9	62	68	84
Ending balance December 31, 2019	123	95	123	95	97
Individually evaluated for impairment
Collectively evaluated for impairment	123	95	123	95	97
Ending balance-total	8,439	9,818	8,439	9,818	10,016
Individually evaluated for impairment
Collectively evaluated for impairment	8,439	9,818	8,439	9,818	10,016
Unallocated Financing Receivables [Member]
Financing Receivable, Past Due [Line Items]
Beginning balance December 31, 2018	611	640	783	646	646
Charge-offs
Recoveries
Provision for loan losses	(3)	(113)	(175)	107	137
Ending balance December 31, 2019	608	753	608	753	783
Individually evaluated for impairment
Collectively evaluated for impairment	608	753	608	753	783
Ending balance-total
Individually evaluated for impairment
Collectively evaluated for impairment

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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