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Interest income recorded.

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Represents the threshold used in determining which loans that have been modified in a troubled debt restructuring are considered impaired and evaluated individually for impairment. All such loans with a principal balance above this threshold are considered impaired and evaluated individually for impairment.

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Represents the number of portfolio segments into which the Company has divided the loan portfolio as of the balance sheet date.

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Represents the percentage of the loan portfolio that is concentrated in a certain category.

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The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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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 on nonaccrual status.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Note 5 - Loans and Allowance for Loan Losses (Details Textual) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 01, 2018 USD ($)	Aug. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of Portfolio Segments	9
Loans Pledged as Collateral	$ 20,400	$ 27,000
Loans and Leases Receivable, Related Parties, Ending Balance	900	800
Loans and Leases Receivable, Related Parties, Additions	100	500
Loans and Leases Receivable, Related Parties, Proceeds	1	200
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance, Total				$ 2,900
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net			$ 2,831	$ 2,800
Certain Loans Acquired in Transfer, Accretable Yield	0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition	0
Loans and Leases Receivable, Gross, Total	513,133	525,870
Financing Receivable, Nonaccrual	1,864	2,759
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,666	708
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	12	44
Interest Income Recorded	6	27
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status	$ 100	$ 100
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Loans Modified in a Troubled Debt Restructuring, Individually Evaluated for Impairment, Principal Balance, Threshold	$ 500
Loans and Leases Receivable, Allowance, Ending Balance	4,924	$ 5,055			$ 4,774
Restructured Loan [Member]
Loans and Leases Receivable, Allowance, Ending Balance	1	2
ALC [Member]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	200	200
Minimum [Member]
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest		500
Minimum [Member] \| ALC [Member]
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest		50
Financial Asset Acquired with Credit Deterioration [Member]
Loans and Leases Receivable, Gross, Total	260	497
Financing Receivable, Nonaccrual	300	500
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	300	500
Loans and Leases Receivable, Allowance, Ending Balance
Financial Asset Acquired with Credit Deterioration [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans and Leases Receivable, Gross, Total	100	300
Financial Asset Acquired with Credit Deterioration [Member] \| Substandard [Member]
Loans and Leases Receivable, Gross, Total	$ 300	$ 500
Real Estate [Member]
Percentage of Loan Portfolio	62.30%	63.20%