Loans, Allowance for Credit Losses, and Asset Quality Information - Summary of Major Categories of Total Loans Outstanding (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 6,526,420	$ 6,083,419
Unamortized net deferred loan fees	(1,134)	(1,704)
Loans	$ 6,525,286	$ 6,081,715
Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	100.00%	100.00%
Total non-PPP SBA loans included in the table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 156,215	$ 171,149
Guaranteed portions of non-PPP SBA loans included in table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	36,625	48,377
Unguaranteed portions of non-PPP SBA loans included in table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	119,590	122,772
Sold portions of SBA loans with servicing retained - not included in tables above
Loans and Leases Receivable Disclosure [Line Items]
Loans	396,108	414,240
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 617,538	$ 648,997
Commercial, financial, and agricultural \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	9.00%	11.00%
Real estate, commercial \| Real estate – construction, land development & other land loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 919,236	$ 828,549
Real estate, commercial \| Real estate – construction, land development & other land loans \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	14.00%	13.00%
Real estate, commercial \| Real estate – mortgage – commercial and other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 3,473,225	$ 3,194,737
Real estate, commercial \| Real estate – mortgage – commercial and other \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	53.00%	53.00%
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,132,552	$ 1,021,966
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	17.00%	17.00%
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 323,218	$ 331,932
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	5.00%	5.00%
Consumer loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 60,651	$ 57,238
Consumer loans \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
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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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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Amount of unamortized loan commitment, origination, and other costs (fees) and purchase premium (discount) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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