Note 5 - Loans (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017
Fair Value of Collateral Dependent Loans as a Percentage of Appraised or Estimated Value of Collateral	85.00%
Allowance for Loan and Lease Losses, Loss Emergence Period	1 year 120 days
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 0
Financing Receivable, Modifications, Number of Contracts	0	0
TDR Loans Transferred to Non-performing, Number of Contracts	1	0
Extension of Credit [Member]
Commitments and Contingencies	$ 79,600
Extension of Lines of Credit [Member]
Commitments and Contingencies	$ 254,800
Commercial Real Estate Portfolio Segment [Member]
Number of Real Estate Classified as Troubled Debt Restructuring Sold	1
Financing Receivable, Modification, Sold During Period	$ 1,800
Loss on Sale of Real Estate Classified as Troubled Debt Restructuring	$ 300
Taxi Medallion Portfolio Segment [Member]
Number of Assets Foreclosed on During the Period	1
Other Repossessed Assets	$ 100
Taxi Medallion Portfolio Segment [Member] \| Other Assets [Member]
Other Repossessed Assets	$ 100

Represents loss emergence period, a period used for calculation allowance for loan and lease losses.

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The fair value of a collateral dependent loan expressed as a percentage of appraised or estimated value of collateral.

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Represents the amount of modified TDR sold during the period.

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Represents the amount of loss on sale of real estate classified as troubled debt restructuring (TDR).

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No definition available.

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Represents number of assets foreclosed on during the period.

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Represents number of real estate which is classified as troubled debt restructuring (TDR) sold during the period.

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No definition available.

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Number of TDR loans transferred to non-performing loans during the period.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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

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Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

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Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

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