Note 3 - Loans Receivable - Classifications of Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loans	$ 428,043	$ 418,991
Less allowance for loan losses	(3,726)	(3,636)	$ (3,298)
Loans, net	424,317	415,355
Construction Loan Portfolio Segment [Member] \| Residential [Member]
Loans	10,429	10,204
Less allowance for loan losses	(67)	(63)	(83)
Construction Loan Portfolio Segment [Member] \| Land Acquisition Development And Commercial [Member]
Loans	29,662	27,480
Less allowance for loan losses	(195)	(173)	(187)
Real Estate Portfolio Segment [Member] \| Residential [Member]
Loans	111,988	111,626
Less allowance for loan losses	(904)	(866)	(1,047)
Real Estate Portfolio Segment [Member] \| Commercial [Member]
Loans	175,654	172,248
Less allowance for loan losses	(1,527)	(1,516)	(1,001)
Commercial Industrial And Agricultural Portfolio Segment Excluding Overdrafts [Member]
Loans	61,591	59,702
Equity Lines Portfolio Segment [Member]
Loans	30,823	29,956
Less allowance for loan losses	(323)	(338)	(277)
Consumer Portfolio Segment [Member]
Loans	7,843	7,668
Less allowance for loan losses	(95)	(97)	$ (85)
Overdrafts Portfolio Segment [Member]
Loans	$ 53	$ 107

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Subparagraph (g)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and 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 and loans held for sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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