Loans and Leases - Age Analysis of Past Due Loans and Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	$ 6,228,442	$ 6,109,877
Nonaccrual loans and lease	11,362	13,353
Total loans and leases held for investment	6,239,804	6,123,230	$ 5,400,786
Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	5,552	14,254
Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,217	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	1,996	875
Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	8,765	16,846
Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	6,219,677	6,093,031
Commercial Financial And Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	1,029,330	1,083,856
Nonaccrual loans and lease	3,423	5,072
Total loans and leases held for investment	1,032,753	1,088,928	942,783
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	1,348	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	0	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	0	0
Commercial Financial And Agricultural [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,348	1,959
Commercial Financial And Agricultural [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,027,982	1,081,897
Real-Estate Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	3,123,922	3,023,418
Nonaccrual loans and lease	4,288	4,537
Total loans and leases held for investment	3,128,210	3,027,955	2,816,737
Real-Estate Commercial [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	328	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	0	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	1,195	20
Real-Estate Commercial [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,523	3,591
Real-Estate Commercial [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	3,122,399	3,019,827
Real-Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	376,186	381,811
Nonaccrual loans and lease	383	0
Total loans and leases held for investment	376,569	381,811	285,083
Real-Estate Construction [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	0	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	0	315
Real-Estate Construction [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	376,186	381,496
Real Estate Residential Secured For Business Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	497,746	477,241
Nonaccrual loans and lease	759	1,013
Total loans and leases held for investment	498,505	478,254	412,486
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	308	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	768	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	1,076	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	496,670	476,400
Real Estate-Residential Secured For Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	778,057	728,406
Nonaccrual loans and lease	1,500	1,989
Total loans and leases held for investment	779,557	730,395	568,735
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	1,506	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	0	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	1,506	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	776,551	723,798
Real Estate Home Equity Secured For Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	171,125	175,959
Nonaccrual loans and lease	948	740
Total loans and leases held for investment	172,073	176,699	160,134
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	835	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	74	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	909	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	170,216	174,781
Loans to Individuals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	28,656	27,873
Nonaccrual loans and lease	0	0
Total loans and leases held for investment	28,656	27,873	26,249
Loans to Individuals [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	20	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	4	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	47	39
Loans to Individuals [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	71	224
Loans to Individuals [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	28,585	27,649
Lease Financings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing loans and leases	223,420	211,313
Nonaccrual loans and lease	61	2
Total loans and leases held for investment	223,481	211,315	$ 188,579
Lease Financings [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	1,207	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	371	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	754	234
Lease Financings [Member] | Financial Asset Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	2,332	4,130
Lease Financings [Member] | Financial Asset Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivables, gross	$ 221,088	$ 207,183