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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, 2024 USD ($) loans loan	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) loans loan	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 0		$ 0		$ 1,000
Reversal of interest income on nonaccrual loans	13	$ 13	75	$ 78
Nonaccrual loans, no allowance	4,500		4,500		1,000
Collateral-dependent loans	$ 11,500		$ 11,500		7,500
Number of loans modified, nonaccrual | loans	3		3
Modified in period, amount			$ 362		506
Restructured loans in default			289	0
Accrued interest receivable on our loan portfolio	$ 21,300		21,300		$ 21,300
Extended Maturity
Financing Receivable, Allowance for Credit Loss [Line Items]
Modified in period, amount	25		$ 25
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
General Loan Term			20 years
Owner and nonowner-occupied real estate	1,850,000		$ 1,850,000
Loans secured by multi-family properties	547,700		547,700
Loans secured by farmland	$ 27,700		$ 27,700
Commercial loans | Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Modified in period, amount				$ 358
Number of loans modified				4
Commercial loans | Extended Maturity
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans modified, nonaccrual | loan	1		1
Commercial loans | Extended Maturity | Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Modified in period, amount				$ 293
Commercial loans | Extended Maturity and Interest Rate Reduction | Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Line Items]
Modified in period, amount				$ 65
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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