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Loans and Allowance for Loan Losses - Narrative (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) loans	Mar. 31, 2023 USD ($) loans	Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 1,200		$ 1,000
Reversal of interest income on nonaccrual loans	34	$ 26
Nonaccrual loans, no allowance	939		1,000
Collateral-dependent loans	10,600		7,500
Restructured loans	535		506
Accrued interest receivable on our loan portfolio	$ 21,500		$ 21,300
Financing Receivable, Excluding Accrued Interest, Modified In Period, Number Of Loans Modified, Nonaccrual | loans	3
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
General Loan Term	20 years
Owner and nonowner-occupied real estate	$ 1,830,000
Loans secured by multi-family properties	551,800
Loans secured by farmland	$ 28,000
Commercial loans | Extended Maturity
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans modified | loans	0
Restructured loans		$ 179
Financing Receivable, Excluding Accrued Interest, Modified In Period, Number Of Loans Modified, Nonaccrual | loans		1
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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