Note 16 - Fair Values (Details Textual)	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 879,000	$ 1,263,000	$ 2,664,000
Impaired Financing Receivable, Related Allowance	203,000	219,000	$ 399,000
Other Repossessed Assets	3,500,000	4,400,000
Real Estate Owned, Valuation Allowance, Amounts Applied	850,000	2,000,000
Impaired Loans [Member]
Impaired Financing Receivable, Related Allowance	203,000	219,000
Impaired Financing Receivable Provision for Loan Losses	0	0
Measured for Impairment Using Fair Value of Collateral [Member]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 879,000	$ 1,300,000
Measurement Input, Discount Rate [Member] \| Minimum [Member]
Impaired Loans, Measurement Input	0.1
Measurement Input, Discount Rate [Member] \| Maximum [Member]
Impaired Loans, Measurement Input	0.33
Measurement Input, Estimated Discount for Cost to Sell [Member] \| Minimum [Member]
Impaired Loans, Measurement Input	0.06
Measurement Input, Estimated Discount for Cost to Sell [Member] \| Maximum [Member]
Impaired Loans, Measurement Input	0.1
Routine Real Estate Collateral [Member] \| Measurement Input, Discount Rate [Member]
Impaired Loans, Measurement Input	0.1
Thin Trading Market or Specialized Collateral [Member] \| Measurement Input, Discount Rate [Member]
Impaired Loans, Measurement Input	0.25

Represents the provision for loan losses on impaired loans.

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- Definition

Value of input used to measure impaired loans.

+ References

No definition available.

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

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- Definition

Amount of the valuation allowance for real estate owned that was applied in the period against the carrying amount of real estate owned that was sold, written down or written off.

+ 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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