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 for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Loans, Allowance for Credit Losses, and Asset Quality Information (Summary of Major Categories of Total Loans Outstanding) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 4,786,846	$ 4,735,013	$ 4,776,911
Unamortized net deferred loan fees		(4,782)	(3,698)	(6,848)
Loans		$ 4,782,064	4,731,315	4,770,063
Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	100.00%	100.00%
SBA Loans
Loans and Leases Receivable Disclosure [Line Items]
Loans		$ 158,695	169,662
SBA Loans, Guaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Loans		32,315	33,959
SBA Loans, Unguaranteed Portion
Loans and Leases Receivable Disclosure [Line Items]
Loans		126,380	135,703
SBA Loans, Sold Portion
Loans and Leases Receivable Disclosure [Line Items]
Loans		426,940	395,398
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 704,096	782,549	723,053
Commercial, financial, and agricultural \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	17.00%	15.00%
Real estate, commercial \| Real estate – construction, land development & other land loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 566,417	570,672	648,590
Real estate, commercial \| Real estate – construction, land development & other land loans \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	12.00%	12.00%
Real estate, commercial \| Real estate – mortgage – commercial and other
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 2,262,492	2,049,203	1,959,078
Real estate, commercial \| Real estate – mortgage – commercial and other \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	43.00%	47.00%
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 914,318	972,378	1,076,411
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	21.00%	19.00%
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 285,595	306,256	318,618
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	6.00%	6.00%
Consumer loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross		$ 53,928	$ 53,955	$ 51,161
Consumer loans \| Loan Category Concentration Risk \| Financing Receivable
Loans and Leases Receivable Disclosure [Line Items]
Percentage	1.00%	1.00%