Loans and Asset Quality Information (Summary of Major Categories of Total Loans Outstanding) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 4,451,525	$ 4,247,765	$ 4,043,355
Unamortized net deferred loan costs	1,941	1,299	(986)
Total loans	$ 4,453,466	$ 4,249,064	4,042,369
Percentage	100.00%	100.00%
SBA Loans
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 165,182	$ 150,777
SBA Loans, Guaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	54,400	53,205
SBA Loans, Unguaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	110,782	97,572
SBA Loans, Sold Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	316,730	230,424
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 504,271	$ 457,037	381,130
Percentage	11.00%	11.00%
Real estate, commercial \| Real estate – construction, land development & other land loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 530,866	$ 518,976	539,020
Percentage	12.00%	12.00%
Real estate, commercial \| Real estate – mortgage – commercial and other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,917,280	$ 1,787,022	1,696,107
Percentage	43.00%	42.00%
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,105,014	$ 1,054,176	972,772
Percentage	25.00%	25.00%
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 337,922	$ 359,162	379,978
Percentage	8.00%	8.00%
Installment loans to individuals
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 56,172	$ 71,392	$ 74,348
Percentage	1.00%	2.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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