Note 3 - Loans and Allowance for Loan Losses - Classes of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Loans	$ 93,817		$ 85,913
Net deferred loan fees, premiums and discounts	(237)		(70)
Undisbursed loans in process	(1,663)		(1,772)
Allowance for loan losses	(1,086)	$ (1,042)	(1,063)	$ (1,196)	$ (1,155)	$ (1,155)
Net loans	90,831		83,008
Residential Portfolio Segment [Member]
Loans	43,989		43,036
Allowance for loan losses	(545)	(578)	(656)	(766)	(739)	(648)
Commercial Real Estate Portfolio Segment [Member]
Loans	38,077		32,175
Allowance for loan losses	(442)	(365)	(326)	(331)	(311)	(383)
Construction and Land Real Estate [Member]
Loans	9,669		9,543
Allowance for loan losses	(76)	(78)	(72)	(88)	(91)	(102)
Commercial Portfolio Segment [Member]
Loans	1,428		383
Allowance for loan losses	(15)	(13)	(4)	(6)	(7)	(19)
Consumer Portfolio Segment [Member]
Loans	654		776
Allowance for loan losses	$ (8)	$ (8)	$ (5)	$ (5)	$ (7)	$ (3)

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.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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 of undisbursed portion of the loan receivable balance (loans in process). 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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