Note 6 - Borrowings - Borrowing (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
FHLB long-term advances maturing 2031	$ 10,000	$ 0
FHLB long-term advances maturing 2031, rate	3.21%	0.00%
Total Borrowing [Member]
Total borrowings	$ 412,000	$ 412,258
Total borrowings, rate	3.34%	3.39%
Repurchase Agreements [Member]
Repurchase agreements	$ 6,609	$ 6,174
Repurchase agreements, rate	5.98%	6.68%
Federal Home Loan Bank of Chicago [Member]
FHLB short-term advances	$ 192,419	$ 216,084
FHLB short-term advances, rate	3.64%	3.69%
FHLB long-term advances maturing 2027	$ 102,972	$ 50,000
FHLB long-term advances maturing 2027, rate	2.52%	1.73%
FHLB long-term advances maturing 2028	$ 10,000	$ 40,000
FHLB long-term advances maturing 2028, rate	3.50%	3.38%
FHLB long-term advances maturing 2029	$ 70,000	$ 60,000
FHLB long-term advances maturing 2029, rate	3.46%	3.48%
FHLB long-term advances maturing 2030	$ 20,000	$ 40,000
FHLB long-term advances maturing 2030, rate	3.29%	3.21%
FHLB advances	$ 405,391	$ 406,084
FHLB advances, rate	3.29%	3.34%

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Weighted average interest rate of debt outstanding.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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