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Loans and Allowance for Loan Losses - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest receivable	$ 28,367,000		$ 39,145,000
Reversal of interest income on nonaccrual loans	12,000	$ 18,000
Nonaccrual loans, no allowance	946,000		1,200,000
Collateral-dependent loans	8,900,000		8,500,000
Commitments to lend additional funds on Troubled Debt Restructurings (TDR)	0	$ 0
Mortgage Loans in Process of Foreclosure, Amount	0		21,000
Accrued interest receivable on our loan portfolio	12,600,000		13,300,000
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Owner and nonowner-occupied real estate	1,440,000,000
Loans secured by multi-family properties	258,400,000
Loans secured by farmland	$ 22,800,000
General Loan Term	20 years
1-4 Family Residential Real Estate Loans | Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
General Loan Term	15 years
1-4 Family Residential Real Estate Loans | Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
General Loan Term	30 years
Paycheck Protection Program
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 13,900,000		$ 31,000,000

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Amount, before allowance for credit loss, of accrued interest on financing receivable.

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