Loans (Aging of past due loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	$ 22,686	$ 17,595
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	22,162	22,085
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	7,476,221	7,141,891
Financing Receivable, 90 Days or More Past Due, Still Accruing	859	1,281
impaired financing receivable recorded investment nonaccrual loans which are current in contractual P and I payments	39,000	58,900
commercial financial agricultural less PPP and overdraft
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	522	378
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	11,629	9,246
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,292,025	1,295,238
PPP Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	9	155
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	0	389
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,116	4,206
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	389
Bank Overdrafts
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	0	0
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	0	0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,499	1,489
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	1,656	737
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	1,839	4,738
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,875,993	1,794,054
Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	0	751
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	205	0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	209,226	208,982
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Construction Real Estate Retail
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	554	1,035
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	26	523
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	95,873	116,433
Financing Receivable, 90 Days or More Past Due, Still Accruing	26	0
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	295	519
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	219	477
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	609,410	550,183
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Residential Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	9,831	7,630
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	6,450	5,157
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,239,861	1,075,446
Financing Receivable, 90 Days or More Past Due, Still Accruing	206	182
Residential Real Estate Home Equity Line Of Credit [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	788	832
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	611	587
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	174,349	167,151
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	7
Residential Real Estate Installment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	52	57
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	0	4
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	5,904	4,091
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	8,974	5,499
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	1,183	964
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,943,869	1,902,831
Check Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	5	2
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	0	0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,067	2,150
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Accruing Loans 30 to 89 Days Past Due	0	0
Financing Receivable Recorded Investment Ninety Days Or More Past Due And Accruing Plus Past Due Nonaccrual Loans	0	0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	24,029	19,637
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financial Asset, Past Due
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	44,848	39,680
Financial Asset, Past Due | commercial financial agricultural less PPP and overdraft
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	12,151	9,624
Financial Asset, Past Due | PPP Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	9	544
Financial Asset, Past Due | Bank Overdrafts
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	0	0
Financial Asset, Past Due | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	3,495	5,475
Financial Asset, Past Due | Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	205	751
Financial Asset, Past Due | Construction Real Estate Retail
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	580	1,558
Financial Asset, Past Due | Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	514	996
Financial Asset, Past Due | Residential Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	16,281	12,787
Financial Asset, Past Due | Residential Real Estate Home Equity Line Of Credit [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,399	1,419
Financial Asset, Past Due | Residential Real Estate Installment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	52	61
Financial Asset, Past Due | Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	10,157	6,463
Financial Asset, Past Due | Check Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	5	2
Financial Asset, Past Due | Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	0	0
Financial Asset, Not Past Due
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	7,431,373	7,102,211
Financial Asset, Not Past Due | commercial financial agricultural less PPP and overdraft
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,279,874	1,285,614
Financial Asset, Not Past Due | PPP Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,107	3,662
Financial Asset, Not Past Due | Bank Overdrafts
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,499	1,489
Financial Asset, Not Past Due | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,872,498	1,788,579
Financial Asset, Not Past Due | Construction Real Estate Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	209,021	208,231
Financial Asset, Not Past Due | Construction Real Estate Retail
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	95,293	114,875
Financial Asset, Not Past Due | Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	608,896	549,187
Financial Asset, Not Past Due | Residential Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,223,580	1,062,659
Financial Asset, Not Past Due | Residential Real Estate Home Equity Line Of Credit [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	172,950	165,732
Financial Asset, Not Past Due | Residential Real Estate Installment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	5,852	4,030
Financial Asset, Not Past Due | Consumer Loan [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,933,712	1,896,368
Financial Asset, Not Past Due | Check Loans
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,062	2,148
Financial Asset, Not Past Due | Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	$ 24,029	$ 19,637