Loans and Asset Quality Information (Summary of Major Categories of Total Loans Outstanding) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 4,776,911	$ 4,451,525	$ 4,337,713
Unamortized net deferred loan costs (fees)	(6,848)	1,941	1,784
Total loans	$ 4,770,063	$ 4,453,466	4,339,497
Percentage	100.00%	100.00%
SBA Loans
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 154,755	$ 165,182
SBA Loans, Guaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	31,630	54,400
SBA Loans, Unguaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	123,125	110,782
SBA Loans, Sold Portion
Loans and Leases Receivable Disclosure [Line Items]
Total loans	347,376	316,730
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 723,053	$ 504,271	471,188
Percentage	15.00%	11.00%
Real estate, commercial \| Real estate – construction, land development & other land loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 648,590	$ 530,866	456,781
Percentage	14.00%	12.00%
Real estate, commercial \| Real estate – mortgage – commercial and other
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 1,959,078	$ 1,917,280	1,900,188
Percentage	41.00%	43.00%
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 1,076,411	$ 1,105,014	1,090,601
Percentage	22.00%	25.00%
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 318,618	$ 337,922	349,355
Percentage	7.00%	8.00%
Consumer loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross	$ 51,161	$ 56,172	$ 69,600
Percentage	1.00%	1.00%

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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