Note 9 - Fair Values Measurement - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Reported Value Measurement [Member]
Cash and cash equivalents	$ 77,048	$ 68,195
Investment securities	100,618	96,704
Loans, net	442,399	396,833
FHLB stock	2,438	2,380
Accrued interest receivable	1,915	2,048
Deposits	581,421	527,276
Repurchase agreements	8,166	7,671
Note payable	2,500	4,875
Junior subordinated deferrable interest debentures	10,310	10,310
Accrued interest payable	57	58
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	77,048	68,195
Investment securities
Loans, net
FHLB stock
Accrued interest receivable	1	26
Deposits	531,832	475,013
Repurchase agreements
Note payable
Junior subordinated deferrable interest debentures
Accrued interest payable	9	8
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Investment securities	100,618	96,704
Loans, net
FHLB stock
Accrued interest receivable	333	328
Deposits	49,572	52,287
Repurchase agreements	8,166	7,671
Note payable
Junior subordinated deferrable interest debentures
Accrued interest payable	36	38
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Investment securities
Loans, net	447,482	395,338
FHLB stock
Accrued interest receivable	1,581	1,694
Deposits
Repurchase agreements
Note payable	2,500	4,875
Junior subordinated deferrable interest debentures	6,210	6,662
Accrued interest payable	12	12
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	77,048	68,195
Investment securities	100,618	96,704
Loans, net	447,482	395,338
Accrued interest receivable	1,915	2,048
Deposits	581,404	527,300
Repurchase agreements	8,166	7,671
Note payable	2,500	4,875
Junior subordinated deferrable interest debentures	6,210	6,662
Accrued interest payable	57	58
Investment securities	$ 100,618	$ 96,704

This item represents the fair value of accrued interest receivable.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

This item represents the fair value of junior subordinated debt obligations.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of trade and related party payables and accrued expenses.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Period Type:	instant

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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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 portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=29638263&loc=d3e39828-111592

+ 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Glossary Loan
-URI http://asc.fasb.org/extlink&oid=6517073

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of notes payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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