Allowance for Credit Losses - Schedule of Non Accrual Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	$ 25,704	$ 21,703
Non accrual, no allowance including guaranteed loans	26,417	22,390
Non accrual including guaranteed loans	30,350	26,864
Total non accrual	29,575	26,053
Past due 90 days or more and still accruing	0	0
Loans Insured or Guaranteed by US Government Authorities
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	713	687
Total non accrual	775	811
Commercial real estate
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	17,571	7,689
Total non accrual	20,412	8,709
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	6,927	9,498
Total non accrual	7,467	11,408
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	1,904	652
Total non accrual	2,416	2,183
Past due 90 days or more and still accruing	0	0
Construction
Financing Receivable, Past Due [Line Items]
Non accrual with no allowance for credit losses	15	4,546
Total non accrual	55	4,546
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	5
Total non accrual	0	18
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
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	7,899	3,110
Total non accrual	7,899	3,110
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	4,763	3,111
Total non accrual	5,036	4,061
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	4,457	0
Total non accrual	4,457	0
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	452	1,468
Total non accrual	3,020	1,538
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	3,594	4,950
Total non accrual	3,595	5,093
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	3,285	4,480
Total non accrual	3,801	6,148
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	48	68
Total non accrual	71	167
Past due 90 days or more and still accruing	$ 0	$ 0