Note 7 - Loans and Related Allowance for Loan Losses - Past Due Financing Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loans, current balance	$ 831,018	$ 605,703
Loans, past due	6,140	3,437
Loans, total	837,158	609,140
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	4,470	2,018
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	506	219
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	1,164	1,200
Commercial And Industrial [Member]
Loans, current balance	90,236	60,407
Loans, past due	1,541	223
Loans, total	91,777	60,630
Commercial And Industrial [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	1,325	17
Commercial And Industrial [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	9	2
Commercial And Industrial [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	207	204
Real Estate Construction Porfolio Segment [Member]
Loans, current balance	29,238	23,709
Loans, past due	0	0
Loans, total	29,238	23,709
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	0	0
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	0	0
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	0	0
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, current balance	296,786	268,041
Loans, past due	3,722	2,789
Loans, total	300,508	270,830
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, current balance	394,255	249,081
Loans, past due	847	409
Loans, total	395,102	249,490
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	2,767	1,909
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	361	92
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	454	207
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	30
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	501	673
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	456	317
Consumer Portfolio Segment [Member]
Loans, current balance	20,503	4,465
Loans, past due	30	16
Loans, total	20,533	4,481
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	17
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	13	10
Consumer Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due		$ 6

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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