Loans, Allowance for Credit Losses, and Asset Quality Information - Schedule of Analysis of Payment Status of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Loans	$ 7,798,963	$ 6,665,145
Nonaccrual loans	28,059	28,514
Unamortized net deferred loan fees	(1,276)	(1,403)
Total	7,800,239	6,666,548
Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	13,323	5,417
Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,468	2,811
Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Current
Financing Receivable, Past Due [Line Items]
Loans	7,757,389	6,629,806
Commercial, financial, and agricultural
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	10,788	10,229
Total	885,032	641,941
Commercial, financial, and agricultural \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,329	438
Commercial, financial, and agricultural \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	392	565
Commercial, financial, and agricultural \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Commercial, financial, and agricultural \| Current
Financing Receivable, Past Due [Line Items]
Loans	872,523	630,709
Commercial, financial, and agricultural \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	885,032	641,941
Real estate, commercial \| Real estate – construction, land development & other land loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	123	1,009
Total	1,092,026	934,176
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	233	238
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	52	1,687
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, commercial \| Real estate – construction, land development & other land loans \| Current
Financing Receivable, Past Due [Line Items]
Loans	1,091,618	931,242
Real estate, commercial \| Real estate – construction, land development & other land loans \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	1,092,026	934,176
Real estate, commercial \| Real estate mortgage – commercial and other
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	12,155	12,505
Total	4,026,258	3,510,261
Real estate, commercial \| Real estate mortgage – commercial and other \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,896	620
Real estate, commercial \| Real estate mortgage – commercial and other \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	725	97
Real estate, commercial \| Real estate mortgage – commercial and other \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, commercial \| Real estate mortgage – commercial and other \| Current
Financing Receivable, Past Due [Line Items]
Loans	4,011,482	3,497,039
Real estate, commercial \| Real estate mortgage – commercial and other \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	4,026,258	3,510,261
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	3,026	3,289
Total	1,386,580	1,195,785
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	8,806	3,415
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	95	25
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages \| Current
Financing Receivable, Past Due [Line Items]
Loans	1,374,653	1,189,056
Real estate, mortgage \| Real estate mortgage – residential (1-4 family) first mortgages \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	1,386,580	1,195,785
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,781	1,397
Total	342,287	323,726
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	807	457
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	139	371
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit \| Current
Financing Receivable, Past Due [Line Items]
Loans	339,560	321,501
Real estate, mortgage \| Real estate mortgage – home equity loans / lines of credit \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	342,287	323,726
Consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	186	85
Total	68,056	60,659
Consumer loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	252	249
Consumer loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	65	66
Consumer loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Consumer loans \| Current
Financing Receivable, Past Due [Line Items]
Loans	67,553	60,259
Consumer loans \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Total	$ 68,056	$ 60,659

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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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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