Note 7 - Federal Home Loan Bank of Indianapolis Advances (Details Textual) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Long-Term Federal Home Loan Bank Advances	$ 447,083	$ 467,910
Line of Credit Facility, Maximum Borrowing Capacity	908,000
Line of Credit Facility, Remaining Borrowing Capacity	464,000
Federal Home Loan Bank of Indianapolis [Member] \| Bullet Advances [member]
Long-Term Federal Home Loan Bank Advances	$ 420,000	$ 440,000
Federal Home Loan Bank of Indianapolis [Member] \| Bullet Advances [member] \| Minimum [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	0.55%	0.55%
Federal Home Loan Bank of Indianapolis [Member] \| Bullet Advances [member] \| Maximum [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	4.54%	5.05%
Federal Home Loan Bank of Indianapolis [Member] \| Bullet Advances [member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	2.96%	2.93%
Federal Home Loan Bank of Indianapolis [Member] \| Amortizing Advances [Member]
Long-Term Federal Home Loan Bank Advances	$ 27,100	$ 27,900
Federal Home Loan Bank of Indianapolis [Member] \| Amortizing Advances [Member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	2.52%	2.52%

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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