Loans and Leases - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	$ 26,141	$ 38,578
Total nonaccrual loans (excluding leases)	25,775
Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	23,369
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,833
None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	573
Commercial Financial And Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	4,208	3,442
Commercial Financial And Agricultural [Member] | Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,802
Commercial Financial And Agricultural [Member] | Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,833
Commercial Financial And Agricultural [Member] | None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	573
Real-Estate Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	17,568	27,928
Real-Estate Commercial [Member] | Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	17,568
Real-Estate Commercial [Member] | Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real-Estate Commercial [Member] | None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Residential Secured For Business Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,754	2,980
Real Estate Residential Secured For Business Purpose [Member] | Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,754
Real Estate Residential Secured For Business Purpose [Member] | Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Residential Secured For Business Purpose [Member] | None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Residential Secured For Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,268	2,038
Real Estate Residential Secured For Personal Purpose [Member] | Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	1,268
Real Estate Residential Secured For Personal Purpose [Member] | Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Residential Secured For Personal Purpose [Member] | None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Home Equity Secured For Personal Purpose [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	977	$ 1,427
Real Estate Home Equity Secured For Personal Purpose [Member] | Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	977
Real Estate Home Equity Secured For Personal Purpose [Member] | Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	0
Real Estate Home Equity Secured For Personal Purpose [Member] | None
Financing Receivable, Allowance for Credit Loss [Line Items]
Total nonaccrual loans	$ 0