Note 9 - Advances From the Federal Home Loan Bank and Other Borrowings (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank Advances Funding Available as Percent of Assets	45.00%
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	$ 455,537,000
Advances from Federal Home Loan Banks, Total	88,350,000	$ 101,357,000
Contingent Letter of Credit with Federal Home Loan Bank, Amount Available	570,000	620,000
Short-term Debt, Average Outstanding Amount	99,307,000	87,283,000
Short-term Debt, Maximum Month-end Outstanding Amount	124,377,000	102,222,000
PNC Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity	10,000,000
Federal Funds Purchased	0	0
Zions Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity	20,000,000
Federal Funds Purchased	0	0
Stockman Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity	7,000,000
PCBB [Member]
Line of Credit Facility, Maximum Borrowing Capacity	10,000,000
Federal Funds Purchased	0	0
United Bankers' Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity	5,000,000
Federal Funds Purchased	$ 0	0
New Markets Tax Credit Loan [Member]
Other Borrowings		$ 865,000
Debt Instrument, Interest Rate During Period		1.00%
Total Borrowings Outstanding [Member]
Debt, Weighted Average Interest Rate	2.18%	2.20%

Amount of contingent letter of credit available from the Federal Home Loan Bank.

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Total Federal Home Loan Bank funding line available as a percent of total assets.

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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.

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The average effective interest rate during the reporting period.

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Weighted average interest rate of debt outstanding.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period.

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