Loans Schedule of loans individually evaluated for impairment by class of loan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance	$ 5,230	$ 2,273
Recorded investment, related to loans	12,700	14,000
Impaired Financing Receivable, Unpaid Principal Balance	78,178	59,381
Impaired Financing Receivable, Recorded Investment	77,491	48,144	$ 56,564
Partial charge-offs on impaired loans	719	11,246
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5,230	2,273
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial charge-offs on impaired loans	500	8,800
Financing Receivable With Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial charge-offs on impaired loans	200	2,400
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	21,194	8,999
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	21,010	3,713
Impaired Financing Receivable, Related Allowance	5,104	2,169
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	12,289	13,736
Recorded investment, related to loans	12,078	11,407
Impaired Financing Receivable, Recorded Investment	33,088	15,120	18,039
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5,104	2,169
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	41,696	26,663
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	41,471	26,213
Impaired Financing Receivable, Related Allowance	35	86
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	320	2,255
Recorded investment, related to loans	320	2,213
Impaired Financing Receivable, Recorded Investment	41,791	28,426	18,142
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	35	86
Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	453	4,679
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	453	1,866
Impaired Financing Receivable, Recorded Investment	453	1,866	1,324
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,921	2,691
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,854	2,374
Impaired Financing Receivable, Related Allowance	42	18
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	171	358
Recorded investment, related to loans	171	358
Impaired Financing Receivable, Recorded Investment	2,025	2,732	$ 19,059
Leases
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance	49
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	134
Recorded investment, related to loans	134
Impaired Financing Receivable, Recorded Investment	134
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 49	$ 0

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-Publisher FASB
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