Loans and Leases - Age Analysis of Past Due Loans and Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	$ 6,562,692	$ 6,109,877
Nonaccrual loans and lease	12,266	13,353
Total loans and leases held for investment	6,574,958	6,123,230	$ 5,849,259
Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	31,803	14,254
Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	2,335	1,717
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	2,135	875
Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	36,273	16,846
Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	6,526,419	6,093,031
Commercial Financial And Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	1,048,593	1,083,856
Nonaccrual loans and lease	1,411	5,072
Total loans and leases held for investment	1,050,004	1,088,928	1,054,940
Commercial Financial And Agricultural [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	9,134	1,616
Commercial Financial And Agricultural [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	249	343
Commercial Financial And Agricultural [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,733	0
Commercial Financial And Agricultural [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	11,116	1,959
Commercial Financial And Agricultural [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,037,477	1,081,897
Real-Estate Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	3,270,277	3,023,418
Nonaccrual loans and lease	4,863	4,537
Total loans and leases held for investment	3,275,140	3,027,955	2,936,204
Real-Estate Commercial [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	5,548	3,281
Real-Estate Commercial [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	335	290
Real-Estate Commercial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	220	20
Real-Estate Commercial [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	6,103	3,591
Real-Estate Commercial [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	3,264,174	3,019,827
Real-Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	427,561	381,811
Nonaccrual loans and lease	0	0
Total loans and leases held for investment	427,561	381,811	329,915
Real-Estate Construction [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	9,450	315
Real-Estate Construction [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	0
Real-Estate Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	0
Real-Estate Construction [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	9,450	315
Real-Estate Construction [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	418,111	381,496
Real Estate Residential Secured For Business Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	515,535	477,241
Nonaccrual loans and lease	936	1,013
Total loans and leases held for investment	516,471	478,254	443,837
Real Estate Residential Secured For Business Purpose [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	2,155	375
Real Estate Residential Secured For Business Purpose [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	650	203
Real Estate Residential Secured For Business Purpose [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	263
Real Estate Residential Secured For Business Purpose [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	2,805	841
Real Estate Residential Secured For Business Purpose [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	512,730	476,400
Real Estate-Residential Secured For Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	856,876	728,406
Nonaccrual loans and lease	4,246	1,989
Total loans and leases held for investment	861,122	730,395	685,771
Real Estate-Residential Secured For Personal Purpose [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	4,042	4,127
Real Estate-Residential Secured For Personal Purpose [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	41	162
Real Estate-Residential Secured For Personal Purpose [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	319
Real Estate-Residential Secured For Personal Purpose [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	4,083	4,608
Real Estate-Residential Secured For Personal Purpose [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	852,793	723,798
Real Estate Home Equity Secured For Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	176,102	175,959
Nonaccrual loans and lease	753	740
Total loans and leases held for investment	176,855	176,699	175,843
Real Estate Home Equity Secured For Personal Purpose [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	445	953
Real Estate Home Equity Secured For Personal Purpose [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	251	225
Real Estate Home Equity Secured For Personal Purpose [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	0
Real Estate Home Equity Secured For Personal Purpose [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	696	1,178
Real Estate Home Equity Secured For Personal Purpose [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	175,406	174,781
Loans to Individuals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	27,331	27,873
Nonaccrual loans and lease	0	0
Total loans and leases held for investment	27,331	27,873	26,679
Loans to Individuals [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	175	32
Loans to Individuals [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	25	153
Loans to Individuals [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	26	39
Loans to Individuals [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	226	224
Loans to Individuals [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	27,105	27,649
Lease Financings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	240,417	211,313
Nonaccrual loans and lease	57	2
Total loans and leases held for investment	240,474	211,315	$ 196,070
Lease Financings [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	854	3,555
Lease Financings [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	784	341
Lease Financings [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	156	234
Lease Financings [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,794	4,130
Lease Financings [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	$ 238,623	$ 207,183