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Loans and Allowance for Loan Losses - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 3,963,041,000		$ 3,963,041,000		$ 3,645,162,000
Interest receivable	41,539,000		41,539,000		39,145,000
Reversal of interest income on nonaccrual loans	24,000	$ 12,000	35,000	$ 25,000
Nonaccrual loans, no allowance	1,300,000		1,300,000		1,200,000
Collateral-dependent loans	9,000,000		9,000,000		8,500,000
Commitments to lend additional funds on Troubled Debt Restructurings (TDR)	0	$ 0	0	$ 0
Mortgage Loans in Process of Foreclosure, Amount	18,000		18,000		21,000
Accrued interest receivable on our loan portfolio	14,600,000		14,600,000		13,300,000
TDRs in default			139,000
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	1,834,734,000		1,834,734,000		1,598,172,000
Owner and nonowner-occupied real estate	1,550,000,000		1,550,000,000
Loans secured by multi-family properties	265,300,000		265,300,000
Loans secured by farmland	21,600,000		$ 21,600,000
General Loan Term			20 years
1-4 Family Residential Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	640,706,000		$ 640,706,000		651,140,000
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	3,000,000		$ 3,000,000		31,000,000
Commercial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 428,974,000		$ 428,974,000		$ 418,998,000

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

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