Note 2 - Fair Value of Financial Instruments - Level 3 Fair Value Measurements (Details) $ in Thousands	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Other Real Estate Owned, Fair Value	$ 822	$ 822
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member]
Other Real Estate Owned, Fair Value	$ 822	822
Impaired Loans, Fair Value		$ 756
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Minimum [Member]
Other Real Estate Owned, Measurement Input	5	5
Impaired Loans, Measurement Input		1.3
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Maximum [Member]
Other Real Estate Owned, Measurement Input	40	40
Impaired Loans, Measurement Input		56
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Weighted Average [Member]
Other Real Estate Owned, Measurement Input	18.1	18.1
Impaired Loans, Measurement Input		32.9
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Nonowner Occupied [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member]
Impaired Loans, Fair Value		$ 216
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Nonowner Occupied [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Minimum [Member]
Impaired Loans, Measurement Input		1.6
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Nonowner Occupied [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Maximum [Member]
Impaired Loans, Measurement Input		50
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Nonowner Occupied [Member] \| Valuation, Market Approach [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Measurement Input, Comparability Adjustment [Member] \| Weighted Average [Member]
Impaired Loans, Measurement Input		26.7

Represents the value of impaired loans as of a specified date.

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

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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=99377789&loc=d3e19207-110258

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