Loan Portfolio and Allowance for Credit Losses, Based on Impairment Review Method (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	$ 0		$ 0
Collectively evaluated for impairment	49,950		48,578
Total ending allowance balance	49,950	$ 49,772	48,578	$ 47,226	$ 46,914	$ 46,032
Loans [Abstract]
Individually evaluated for impairment	25,055		24,729
Collectively evaluated for impairment	5,045,801		4,978,150
Total loans	5,070,856		5,002,879
Commercial Loans [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3,352		2,735
Total ending allowance balance	3,352	3,429	2,735	2,713	2,610	2,596
Loans [Abstract]
Individually evaluated for impairment	882		957
Collectively evaluated for impairment	279,379		272,558
Total loans	280,261		273,515
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	46,392		45,625
Total ending allowance balance	46,392	46,129	45,625	44,285	44,067	43,271
Loans [Abstract]
Individually evaluated for impairment	24,043		23,628
Collectively evaluated for impairment	4,752,049		4,688,850
Total loans	4,776,092		4,712,478
Installment Loans [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	206		218
Total ending allowance balance	206	$ 214	218	$ 228	$ 237	$ 165
Loans [Abstract]
Individually evaluated for impairment	130		144
Collectively evaluated for impairment	14,373		16,742
Total loans	$ 14,503		$ 16,886