Note 7 - Fair Value Measurement - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financial assets
Securities available for sale	$ 52,159	$ 52,975
Reported Value Measurement [Member]
Financial assets
Cash and due from banks	28,005	18,229
Federal funds sold	51	42
Securities available for sale	52,159	52,975
Restricted equity securities	2,290	2,213
Loans held for sale	123	678
Loans, net	424,317	415,355
Bank owned life insurance	7,517	7,469
Accrued income	2,250	2,289
Financial liabilities
Total deposits	464,645	450,848
FHLB borrowings	9,917	8,000
Subordinated notes	7,232	7,224
Other borrowings	1,121	1,117
Accrued interest payable	520	386
Estimate of Fair Value Measurement [Member]
Financial assets
Cash and due from banks	28,015	18,239
Federal funds sold	51	42
Securities available for sale	52,159	52,975
Restricted equity securities	2,290	2,213
Loans held for sale	123	678
Loans, net	426,873	415,039
Bank owned life insurance	7,517	7,469
Accrued income	2,250	2,289
Financial liabilities
Total deposits	465,188	451,385
FHLB borrowings	9,919	8,031
Subordinated notes	8,033	8,012
Other borrowings	1,121	1,117
Accrued interest payable	520	386
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets
Cash and due from banks	27,255	17,479
Federal funds sold	51	42
Securities available for sale
Restricted equity securities
Loans held for sale
Loans, net
Bank owned life insurance
Accrued income
Financial liabilities
Total deposits
FHLB borrowings
Subordinated notes
Other borrowings
Accrued interest payable
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets
Cash and due from banks	760	760
Federal funds sold
Securities available for sale	52,159	52,975
Restricted equity securities	2,290	2,213
Loans held for sale	123	678
Loans, net
Bank owned life insurance	7,517	7,469
Accrued income	2,250	2,289
Financial liabilities
Total deposits	465,188	451,385
FHLB borrowings	9,919	8,031
Subordinated notes	8,033	8,012
Other borrowings	1,121	1,117
Accrued interest payable	520	386
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets
Cash and due from banks
Federal funds sold
Securities available for sale
Restricted equity securities
Loans held for sale
Loans, net	426,873	415,039
Bank owned life insurance
Accrued income
Financial liabilities
Total deposits
FHLB borrowings
Subordinated notes
Other borrowings
Accrued interest payable

The fair value portion of accrued income.

No definition available.

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- Definition

The fair value portion of accrued interest payable.

+ References

No definition available.

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- Definition

The fair value portion of bank owned life insurance.

+ References

No definition available.

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- Definition

Fair value portion of cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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- Definition

The carrying amount of securities categorized neither as held-to-maturity nor trading which serve as security for borrowings or other arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(f))
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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value portion of federal funds sold and securities borrowed or purchased under agreements to resell.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ References

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- References

No definition available.

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Period Type:	duration

- References

No definition available.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Publisher FASB
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-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Fair value portion of other liabilities.

+ References

No definition available.

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