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Note 15 - Commitments and Contingencies (Details Textual) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Off-Balance-Sheet, Credit Loss, Liability | $ 7,500 | $ 7,400
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | (81,000) | 2,200
Federal Home Loan Bank of Des Moines [Member] |  |
Letters of Credit Outstanding, Amount | $ 12,000 | 0
Federal Home Loan Bank (FHLB) [Member] |  |
Letters of Credit, Number Outstanding | 5 |
Bank of North Dakota [Member] |  |
Letters of Credit, Number Outstanding | 1 |
Letters of Credit Outstanding, Amount | $ 50,000 | 182,000
Bank of North Dakota [Member] | Letter of Credit [Member] |  |
Debt Instrument, Collateral Amount | 524,900 | 454,600
Unfunded Loan Commitment [Member] |  |
Off-Balance-Sheet, Credit Loss, Liability | 7,500 | 7,400
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | $ 100 | $ 2,200

X
- Definition The number of outstanding letters of credit. + References No definition available. + Details
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X
- 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 -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
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X
- Definition 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 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482454/460-10-45-1 + Details
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- Definition 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 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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