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Note 4 - Loans and Allowance for Credit Losses - Schedule of Modified Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction	$ 0	$ 0		$ 0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member]
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage			2.20%
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Contractual Interest Rate Reduction [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			$ 0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Principal Forgiveness [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Payment Deferral [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			1,463
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity and Principal Forgiveness [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity and Interest Rate Reduction [Member]
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction			$ 0

X

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

X

- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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