Loans - Schedule of recorded investment in nonaccrual restructured and loans 90 days past due and accruing (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	$ 79,696	$ 72,722
Financing Receivable, Troubled Debt Restructuring	20,134	28,323
Financing Receivable, 90 Days or More Past Due, Still Accruing	1,281	1,607
Financing Receivable Recorded Investment Nonperforming	101,111	102,652
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	38,158	13,271
Financing Receivable, Troubled Debt Restructuring	3,261	9,396
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	41,419	22,667
PPP Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	0	0
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	389	793
Financing Receivable Recorded Investment Nonperforming	389	793
Bank Overdrafts
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	0	0
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	0	0
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	24,504	40,142
Financing Receivable, Troubled Debt Restructuring	7,919	7,713
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	32,423	47,855
Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,712	52
Financing Receivable, Troubled Debt Restructuring	0	169
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	1,712	221
Construction Real Estate Retail
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,254
Financing Receivable, Troubled Debt Restructuring	12
Financing Receivable, 90 Days or More Past Due, Still Accruing	0
Financing Receivable Recorded Investment Nonperforming	1,266
Construction Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual		716
Financing Receivable, Troubled Debt Restructuring		9
Financing Receivable, 90 Days or More Past Due, Still Accruing		0
Financing Receivable Recorded Investment Nonperforming		725
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,894	2,366
Financing Receivable, Troubled Debt Restructuring	298	240
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	2,192	2,606
Residential Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	9,260	11,718
Financing Receivable, Troubled Debt Restructuring	6,750	7,779
Financing Receivable, 90 Days or More Past Due, Still Accruing	182	372
Financing Receivable Recorded Investment Nonperforming	16,192	19,869
Residential Real Estate Home Equity Line Of Credit [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,133	1,590
Financing Receivable, Troubled Debt Restructuring	187	803
Financing Receivable, 90 Days or More Past Due, Still Accruing	7	0
Financing Receivable Recorded Investment Nonperforming	1,327	2,393
Residential Real Estate Installment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	51	82
Financing Receivable, Troubled Debt Restructuring	1,037	1,508
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	1,088	1,590
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	1,012	1,518
Financing Receivable, Troubled Debt Restructuring	670	700
Financing Receivable, 90 Days or More Past Due, Still Accruing	703	431
Financing Receivable Recorded Investment Nonperforming	2,385	2,649
GFSC loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	10	79
Financing Receivable, Troubled Debt Restructuring	0	6
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	11
Financing Receivable Recorded Investment Nonperforming	10	96
Check Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	0	0
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	0	0
Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Nonaccrual	708	1,188
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable Recorded Investment Nonperforming	$ 708	$ 1,188