Note 11 - Fair Value and Interest Rate Risk - Quantitative Information About Level 3 Fair Value Measurements (Details) - Fair Value, Inputs, Level 3 [Member] $ in Thousands	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
SBA Servicing Assets	$ 156	$ 37
Fair Value of Collateral Approach [Member]
Impaired loans, net	20,993	19,673
Other Real Estate Owned	$ 1,954	$ 2,945
Fair Value of Collateral Approach [Member] \| Measurement Input, Discount Rate [Member]
Other Real Estate Owned	0.14	0.14
Fair Value of Collateral Approach [Member] \| Minimum [Member] \| Measurement Input, Discount Rate [Member]
Impaired loans, net	0.08	0.08
Fair Value of Collateral Approach [Member] \| Maximum [Member] \| Measurement Input, Discount Rate [Member]
Impaired loans, net	0.21	0.21
Valuation Technique, Discounted Cash Flow [Member]
SBA Servicing Assets	$ 156
Valuation Technique, Discounted Cash Flow [Member] \| Minimum [Member] \| Measurement Input, Discount Rate [Member]
SBA Servicing Assets	0.1473
Valuation Technique, Discounted Cash Flow [Member] \| Maximum [Member] \| Measurement Input, Discount Rate [Member]
SBA Servicing Assets	0.149

Fair value portion of impaired loans receivable.

No definition available.

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- Definition

Value of input used to measure impaired loans.

+ References

No definition available.

+ Details

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- Definition

Represents the fair value of other real estate owned.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

+ Details

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- Definition

Value of input used to measure servicing asset.

+ References

+ Details

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- Details

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