Note 12 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
|
| Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | $ 67 | $ 1,200 | $ 400 | $ 2,700 | |
| Bank of North Dakota [Member] | |||||
| Letters of Credit Outstanding, Amount | 0 | 0 | $ 126,000 | ||
| Bank of North Dakota [Member] | Line of Credit [Member] | |||||
| Debt Instrument, Collateral Amount | 511,400 | 511,400 | 549,000 | ||
| Federal Home Loan Bank of Des Moines [Member] | |||||
| Letters of Credit Outstanding, Amount | 17,500 | 17,500 | 33,600 | ||
| Unfunded Loan Commitment [Member] | |||||
| Off-Balance-Sheet, Credit Loss, Liability | $ 3,500 | 3,500 | $ 3,900 | ||
| Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | $ (400) | $ (2,700) | |||