Loans and Leases - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	$ 31,692	$ 38,578
Nonaccrual loans (excluding leases)	31,485
Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	2,827	3,442
Real Estate-Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	22,739	27,928
Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	2,786	2,980
Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	2,086	2,038
Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	1,047	$ 1,427
Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	30,009
Real Estate [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	1,351
Real Estate [Member] | Real Estate-Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	22,739
Real Estate [Member] | Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	2,786
Real Estate [Member] | Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	2,086
Real Estate [Member] | Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	1,047
Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	1,194
Other [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	1,194
Other [Member] | Real Estate-Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
Other [Member] | Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
Other [Member] | Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
Other [Member] | Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
None [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	282
None [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	282
None [Member] | Real Estate-Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
None [Member] | Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
None [Member] | Real Estate-Residential Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	0
None [Member] | Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Nonaccrual loans	$ 0