Allowance for Credit Losses - Schedule of Non Accrual Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	$ 11,206	$ 25,704
Non accrual, no allowance including guaranteed loans	11,316	26,417
Non accrual including guaranteed loans	17,466	30,350
Total non accrual	17,319	29,575
Past due 90 days or more and still accruing	5	0
Loans Insured or Guaranteed by US Government Authorities
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	110	713
Total non accrual	147	775
Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	4,680	17,571
Total non accrual	4,637	20,412
Past due 90 days or more and still accruing	0	0
Consumer
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	6,054	6,927
Total non accrual	6,681	7,467
Past due 90 days or more and still accruing	0	0
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	462	1,904
Total non accrual	655	2,416
Past due 90 days or more and still accruing	5	0
Construction
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	120	15
Total non accrual	120	55
Past due 90 days or more and still accruing	0	0
Agriculture production
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	0	0
Total non accrual	5,373	0
Past due 90 days or more and still accruing	0	0
Leases
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	0	0
Total non accrual	0	0
Past due 90 days or more and still accruing	0	0
CRE non-owner occupied | Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	2,032	7,899
Total non accrual	2,032	7,899
Past due 90 days or more and still accruing	0	0
CRE owner occupied | Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	1,703	4,763
Total non accrual	1,778	5,036
Past due 90 days or more and still accruing	0	0
Multifamily | Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	132	4,457
Total non accrual	132	4,457
Past due 90 days or more and still accruing	0	0
Farmland | Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	813	452
Total non accrual	695	3,020
Past due 90 days or more and still accruing	0	0
SFR 1-4 1st DT liens | Consumer
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	3,103	3,594
Total non accrual	3,255	3,595
Past due 90 days or more and still accruing	0	0
SFR HELOCs and junior liens | Consumer
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	2,945	3,285
Total non accrual	3,365	3,801
Past due 90 days or more and still accruing	0	0
Other | Consumer
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	6	48
Total non accrual	61	71
Past due 90 days or more and still accruing	$ 0	$ 0