Loan Portfolio and Allowance for Credit Losses, Based on Impairment Review Method (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	$ 0	$ 0
Collectively evaluated for impairment	46,685	46,032
Total ending allowance balance	46,685	46,032	$ 46,178
Loans [Abstract]
Individually evaluated for impairment	25,001	25,695
Collectively evaluated for impairment	4,774,581	4,707,506
Total loans	4,799,582	4,733,201
Commercial [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,708	2,596
Total ending allowance balance	2,708	2,596	2,177
Loans [Abstract]
Individually evaluated for impairment	986	646
Collectively evaluated for impairment	245,321	230,365
Total loans	246,307	231,011
1 to 4 Family Residential Real Estate [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	43,766	43,271
Total ending allowance balance	43,766	43,271	43,931
Loans [Abstract]
Individually evaluated for impairment	23,934	24,967
Collectively evaluated for impairment	4,514,015	4,464,916
Total loans	4,537,949	4,489,883
Installment [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	211	165
Total ending allowance balance	211	165	$ 70
Loans [Abstract]
Individually evaluated for impairment	81	82
Collectively evaluated for impairment	15,245	12,225
Total loans	$ 15,326	$ 12,307