Loans Schedule of loans individually evaluated for impairment by class of loan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance	$ 5,434,000	$ 5,230,000
Recorded investment, related to loans	13,900,000	12,700,000
Impaired Financing Receivable, Unpaid Principal Balance	109,062,000	78,178,000
Impaired Financing Receivable, Recorded Investment	108,455,000	77,491,000	$ 48,144,000
Partial charge-offs on impaired loans	655,000	719,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5,434,000	5,230,000
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial charge-offs on impaired loans	600,000	500,000
Financing Receivable With Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial charge-offs on impaired loans	16,000	210,000
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	23,316,000	21,194,000
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	22,970,000	21,010,000
Impaired Financing Receivable, Related Allowance	3,758,000	5,104,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,881,000	12,289,000
Recorded investment, related to loans	5,866,000	12,078,000
Impaired Financing Receivable, Recorded Investment	28,836,000	33,088,000	15,120,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	3,758,000	5,104,000
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	63,639,000	41,696,000
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	63,467,000	41,471,000
Impaired Financing Receivable, Related Allowance	1,316,000	35,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	6,890,000	320,000
Recorded investment, related to loans	6,890,000	320,000
Impaired Financing Receivable, Recorded Investment	70,357,000	41,791,000	28,426,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,316,000	35,000
Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	3,110,000	453,000
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	3,110,000	453,000
Impaired Financing Receivable, Recorded Investment	3,110,000	453,000	1,866,000
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	4,522,000	1,921,000
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	4,448,000	1,854,000
Impaired Financing Receivable, Related Allowance	16,000	42,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	109,000	171,000
Recorded investment, related to loans	109,000	171,000
Impaired Financing Receivable, Recorded Investment	4,557,000	2,025,000	$ 2,732,000
Leases
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	568,000
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	568,000
Impaired Financing Receivable, Related Allowance	344,000	49,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	1,027,000	134,000
Recorded investment, related to loans	1,027,000	134,000
Impaired Financing Receivable, Recorded Investment	1,595,000	134,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 344,000	$ 49,000