Loans, Allowance for Credit Losses, and Asset Quality Information - Summary of Major Categories of Total Loans Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 7,800,239	$ 6,666,548
Unamortized net deferred loan fees	(1,276)	(1,403)
Loans	$ 7,798,963	$ 6,665,145
Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	100.00%	100.00%
Total SBA loans included in the table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 151,448	$ 148,803
Guaranteed portions of SBA loans included in table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	36,035	31,893
Unguaranteed portions of SBA loans included in table above
Loans and Leases Receivable Disclosure [Line Items]
Loans	115,413	116,910
Sold portions of SBA loans with servicing retained - not included in tables above
Loans and Leases Receivable Disclosure [Line Items]
Loans	380,634	392,370
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 885,032	$ 641,941
Commercial, financial, and agricultural \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	11.00%	9.00%
Real estate, commercial \| Real estate – construction, land development & other land loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,092,026	$ 934,176
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%	14.00%
Real estate, commercial \| Real estate mortgage – commercial and other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 4,026,258	$ 3,510,261
Real estate, commercial \| Real estate mortgage – commercial and other \| Financing Receivable \| Loan Category Concentration Risk
Loans and Leases Receivable Disclosure [Line Items]
Percentage	52.00%	53.00%
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,386,580	$ 1,195,785
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	18.00%	18.00%
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 342,287	$ 323,726
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	4.00%	5.00%
Consumer loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 68,056	$ 60,659
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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