Note 13 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	$ 549	$ 31	$ 44
Advance from Federal Home Loan Bank	0	0		$ 0
Bank of North Dakota [Member]
Letters of Credit Outstanding, Amount	150,000	150,000		182,000
Bank of North Dakota [Member] \| Letter of Credit [Member]
Debt Instrument, Collateral Amount	$ 469,100	469,100		454,600
Unfunded Loan Commitment [Member]
Off-Balance-Sheet, Credit Loss, Liability				$ 7,400
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)		$ (31)	$ 44

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478878/942-470-45-1

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- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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-Publisher FASB
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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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