Note 8 - Other Real Estate Owned (OREO) (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Number of Loans Transferred to OREO	7
Real Estate Owned, Transfer to Real Estate Owned	$ 981	$ 147	$ 3,888
Other Real Estate Owned, Costs Capitalized	$ 90
Number of Real Estate Properties Sold	11
Sales of Real Estate	$ 1,700
Gains (Losses) on Sales of Other Real Estate	$ 368	$ (109)	$ 13
Number of Writedown Real Estate Properties	1
Impairment of Real Estate	$ 52
Residential One to Four Family [Member]
Number of Real Estate Properties	1
Real Estate Acquired Through Foreclosure	$ 35

Number of loans transferred from mortgage loans to real estate owned (REO) in noncash transactions.

No definition available.

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- Definition

The number of real estate properties sold during the period.

+ References

No definition available.

+ Details

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- Definition

The number of write-down real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of costs capitalized during the period.

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
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-Paragraph 2
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Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

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-Publisher FASB
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- Definition

Revenue from the sale of commercial, industrial, or residential property during the period. This element is more likely than not relevant to an entity for which real estate operations are a principal activity. If real estate operations are not a principal activity, the reporting entity would likely use a gain (loss) on sale of property, plant, or equipment type element.

+ References

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- Definition

Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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