Loans and Allowance - Summary of Non-Accrual Loans by Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	$ 57,556	$ 61,471
Non-Accrual Loans with no Allowance for Credit Losses	31,264
Commercial and industrial loans
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	1,467	2,329
Non-Accrual Loans with no Allowance for Credit Losses	781
Agricultural land, production and other loans to farmers
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	682	1,012
Non-Accrual Loans with no Allowance for Credit Losses	562
Construction
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	1	123
Non-Accrual Loans with no Allowance for Credit Losses	0
Commercial real estate, non-owner occupied
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	45,437	46,316
Non-Accrual Loans with no Allowance for Credit Losses	28,179
Commercial real estate, owner occupied
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	2,133	3,040
Non-Accrual Loans with no Allowance for Credit Losses	926
Residential
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	5,552	6,517
Non-Accrual Loans with no Allowance for Credit Losses	816
Home equity
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	2,248	2,095
Non-Accrual Loans with no Allowance for Credit Losses	0
Individuals' loans for household and other personal expenditures
Financing Receivable, Past Due [Line Items]
Non-Accrual Loans	36	$ 39
Non-Accrual Loans with no Allowance for Credit Losses	$ 0