Note 15 - Assets and Liabilities Measured and Reported at Fair Value - Assets Measured at Fair Value on a Non-recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Other real estate owned losses	$ 109
Fair Value, Measurements, Nonrecurring [Member]
Impaired loans	5,918	2,569
Impaired loans losses	(1,711)	(452)
Other real estate owned	360	2,640
Other real estate owned losses
Assets, Fair Value Disclosure	6,278	5,209
Total losses	(1,711)	(452)
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans
Other real estate owned
Assets, Fair Value Disclosure
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans
Other real estate owned
Assets, Fair Value Disclosure
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans	5,918	2,569
Other real estate owned	360	2,640
Assets, Fair Value Disclosure	$ 6,278	$ 5,209

Represents the amount of losses representing change in assets fair value disclosure allowances.

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- Definition

The fair value related to impaired financing receivables.

+ References

No definition available.

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- Definition

Represents the amount of losses representing change in specific allowances.

+ References

No definition available.

+ Details

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- Definition

The fair value related to other real assets owned fair value disclosure.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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