Note 5 - Loans (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Gain (Loss) on Sales of Loans, Net, Total	$ 253	$ 210
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Ending Balance	$ 1,061	820
Loans Still Classified as Non-accrual Status, Period of Past Due	90 days
Financing Receivable, Nonaccrual	$ 9,100	4,700
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Evaluated Individually for Impairment, Non-accrued Loans Other Than TDRs, Threshold	100
Financing Receivable, Collectively Evaluated for Impairment	810,570	822,790
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	400	200
Financing Receivable, Troubled Debt Restructuring	9,100	9,200
Loans and Leases Receivable, Allowance, Ending Balance	8,950	9,519
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0	$ 0
Financing Receivable, Modifications, Number of Contracts	10	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Residential Portfolio Segment [Member]
Financing Receivable, Modifications, Number of Contracts	4
Number of Real Estate Properties in Process of Foreclosure	1
Real Estate Investment Property in Process of Foreclosure	$ 154
Real Estate Investment Property, Foreclosed		$ 0
Real Estate Investment Property, Net, Total	$ 204	$ 45
Number of Real Estate Properties in OREO	1	1
Residential Portfolio Segment [Member] \| Investor-owned Real Estate Loan [Member]
Number of Real Estate Properties, Foreclosed	2
Real Estate Investment Property, Foreclosed	$ 256
Consumer Portfolio Segment [Member]
Financing Receivable, Collectively Evaluated for Impairment	$ 138,044	$ 176,401
Financing Receivable, Modifications, Number of Contracts
Mortgage Loans in Process of Foreclosure, Number		2
Mortgage Loans in Process of Foreclosure, Amount		$ 0
Troubled Debt Restructuring [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 97	651
Nonaccrual Loans [Member]
Financing Receivable, Collectively Evaluated for Impairment	1,000	700
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring	7,700	8,500
Nonperforming Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring	1,400	700
Small Business Administration [Member]
Gain (Loss) on Sales of Loans, Net, Total		322
Loans Sold During Period, Principal Balance	0	5,700
Loans Serviced for Others, Unpaid Principal Balance	106,000	108,400
One- to Four-family Mortgages [Member]
Recorded Investment of Mortgage Loans Sold	9,600
Gain (Loss) on Sales of Loans, Net, Total	253	210
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Ending Balance	$ 1,100	$ 820

The threshold value for non-accrued loans other than TDRs to be evaluated individually for impairment.

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The number of mortgage loans that are in process of foreclosure.

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The number of real estate properties in process of foreclosure as of the balance sheet date.

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The amount of the outstanding recorded investment related to mortgage loans sold during the period.

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The balance of financing receivables that were collectively evaluated for impairment.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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