Loans And Allowance For Credit Losses - Schedule of Non-Accrual Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	$ 31,652	$ 42,619
Commercial [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	5,370	5,015
Commercial [Member] | C&I [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	5,370	5,015
Agricultural [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	4,920	1,076
Real Estate [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	20,809	36,028
Real Estate [Member] | Construction & Development [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	708	3,838
Real Estate [Member] | Farm [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	1,173	7,299
Real Estate [Member] | Non - Owner Occupied CRE [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	2,671	5,243
Real Estate [Member] | Owner Occupied CRE [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	7,897	10,797
Real Estate [Member] | Residential [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	8,360	8,851
Consumer [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	553	500
Consumer [Member] | Auto [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	514	407
Consumer [Member] | Non - Auto [Member]
Loans And Leases Receivable Disclosure [Line Items]
Non-accrual loans	$ 39	$ 93