Loans and Related Allowance for Credit Losses (Nonaccrual Loans by Classes of the Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Financing receivable, recorded investment, nonaccrual status	$ 4,964	$ 1,819
Commercial, Financial and Agricultural [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing receivable, recorded investment, nonaccrual status	562
Commercial Loan [Member] | Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing receivable, recorded investment, nonaccrual status	3,537	903
Mortgage Loan [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing receivable, recorded investment, nonaccrual status	$ 865	902
Personal Loan [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Financing receivable, recorded investment, nonaccrual status		$ 14