Loan Portfolio and Allowance for Credit Losses, Based on Impairment Review Method (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	$ 0		$ 0
Collectively evaluated for impairment	45,517		44,267
Total ending allowance balance	45,517		44,267	$ 47,350		$ 49,595
Total ending allowance balance		$ 45,285	44,267	47,350	$ 50,155
Loans [Abstract]
Individually evaluated for impairment	26,467		18,504
Collectively evaluated for impairment	4,603,024		4,420,275
Total loans	4,629,491
Total loans			4,438,779
Commercial [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,429		3,135
Total ending allowance balance	2,429		3,135	3,253		4,140
Total ending allowance balance		2,274	3,135	3,253	4,106
Loans [Abstract]
Individually evaluated for impairment	294		232
Collectively evaluated for impairment	216,826		199,968
Total loans	217,120
Total loans			200,200
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	42,944		40,689
Total ending allowance balance	42,944		40,689	43,653		44,950
Total ending allowance balance		42,880	40,689	43,653	45,617
Loans [Abstract]
Individually evaluated for impairment	26,157		18,272
Collectively evaluated for impairment	4,375,549		4,210,891
Total loans	4,401,706
Total loans			4,229,163
Installment [Member]
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	144		443
Total ending allowance balance	144		443	444		$ 505
Total ending allowance balance		$ 131	443	$ 444	$ 432
Loans [Abstract]
Individually evaluated for impairment	16		0
Collectively evaluated for impairment	10,649		9,416
Total loans	$ 10,665
Total loans			$ 9,416