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Loans and Allowance for Loan Losses - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($) loans	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) loans	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 63		$ 63		$ 0
Reversal of interest income on nonaccrual loans	13	$ 10	78	$ 33
Nonaccrual loans, no allowance	1,000		1,000		1,600
Collateral-dependent loans	7,700		7,700		8,100
Restructured loans					897
Accrued interest receivable on our loan portfolio	20,300		20,300		$ 18,800
Amortization Period Extension
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans			$ 343
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
General Loan Term			20 years
Owner and nonowner-occupied real estate	1,750,000		$ 1,750,000
Loans secured by multi-family properties	339,400		339,400
Loans secured by farmland	$ 29,400		$ 29,400
Commercial loans | Amortization Period Extension
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans modified | loans	3		3
Restructured loans			$ 343
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

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