Note 4 - Loans (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Gain (Loss) on Sales of Loans, Net, Total	$ 96	$ 56
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	$ 470		$ 1,061
Loans Still Classified as Non-accrual Status, Period of Past Due (Day)	90 days
Financing Receivable, Nonaccrual	$ 8,600		9,100
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	818,029		810,570
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	111	$ 82
Financing Receivable, Troubled Debt Restructuring	9,000		9,100
Loans and Leases Receivable, Allowance, Ending Balance	9,907		8,950
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0
Financing Receivable, Modifications, Number of Contracts	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Number of Payment Deferrals	266
Financing Receivable, Deferred Payments	$ 88,000
Residential Portfolio Segment [Member]
Number of Real Estate Properties in OREO	0	1
Real Estate Investment Property, Foreclosed	$ 0	$ 0
Real Estate Investment Property, Net, Total		$ 45
Consumer Portfolio Segment [Member]
Financing Receivable, Collectively Evaluated for Impairment	$ 129,000		138,044
Mortgage Loans in Process of Foreclosure, Number	0	3
Mortgage Loans in Process of Foreclosure, Amount		$ 0
Troubled Debt Restructuring [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 65		97
Nonaccrual Loans [Member]
Financing Receivable, Collectively Evaluated for Impairment	1,200		1,000
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring	7,700		7,700
Nonperforming Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring	1,300		1,400
Small Business Administration [Member]
Loans Sold During Period, Principal Balance	0	0
Loans Serviced for Others, Unpaid Principal Balance	105,700		106,000
One- to Four-family Mortgages [Member]
Recorded Investment of Mortgage Loans Sold	2,900	1,900
Gain (Loss) on Sales of Loans, Net, Total	96	$ 56
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	$ 500		$ 1,100

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

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Deferred amounts on loans receivable related to loan modification programs offered to financial institution customers affected by COVID-19.

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The amount of loans sold during the period.

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Represents the number of days past due at which a loan is transferred to non-accrual status.

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

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Represents the number of real estate properties included in other real estate owned as of the balance sheet date.

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The value of real estate investment property that were foreclosed during the period.

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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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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of financing receivable 90 days or more past due and still accruing.

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Amount of financing receivable on nonaccrual status.

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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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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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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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