Note 4 - Allowance for Loan Losses (Details) - Allowance for Loan Losses - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Construction loans:
Allowance for loan losses, beginning balance	$ 3,298	$ 3,332
Allowance for loan losses, charge-offs	(15)	(80)
Allowance for loan losses, recoveries	4	46
Allowance for loan losses, provisions	60
Allowance for loan losses, ending balance	3,347	3,298
Allowance for loan losses, ending balance: individually evaluated for impairment	17	17
Allowance for loan losses, ending balance: collectively evaluated for impairment	3,330	3,281
Loans	381,063	367,358
Loans,ending balance: individually evaluated for impairment	7,807	7,837
Loans, ending balance: collectively evaluated for impairment	373,256	359,521
Construction Loan Portfolio Segment [Member] \| Residential [Member]
Construction loans:
Allowance for loan losses, beginning balance	83	43
Allowance for loan losses, provisions	(6)	40
Allowance for loan losses, ending balance	77	83
Allowance for loan losses, ending balance: collectively evaluated for impairment	77	83
Loans	10,983	11,779
Loans, ending balance: collectively evaluated for impairment	10,983	11,779
Construction Loan Portfolio Segment [Member] \| Land Acquisition, Development and Commercial [Member]
Construction loans:
Allowance for loan losses, beginning balance	187	453
Allowance for loan losses, provisions	33	(266)
Allowance for loan losses, ending balance	220	187
Allowance for loan losses, ending balance: collectively evaluated for impairment	220	187
Loans	30,167	27,440
Loans, ending balance: collectively evaluated for impairment	30,167	27,440
Real Estate Portfolio Segment [Member] \| Residential [Member]
Construction loans:
Allowance for loan losses, beginning balance	1,047	833
Allowance for loan losses, recoveries		1
Allowance for loan losses, provisions	(7)	213
Allowance for loan losses, ending balance	1,040	1,047
Allowance for loan losses, ending balance: collectively evaluated for impairment	1,040	1,047
Loans	105,055	100,268
Loans,ending balance: individually evaluated for impairment	195	247
Loans, ending balance: collectively evaluated for impairment	104,860	100,021
Real Estate Portfolio Segment [Member] \| Commercial [Member}
Construction loans:
Allowance for loan losses, beginning balance	1,001	1,012
Allowance for loan losses, provisions	95	(11)
Allowance for loan losses, ending balance	1,096	1,001
Allowance for loan losses, ending balance: individually evaluated for impairment	17	17
Allowance for loan losses, ending balance: collectively evaluated for impairment	1,079	984
Loans	147,561	140,952
Loans,ending balance: individually evaluated for impairment	7,600	7,578
Loans, ending balance: collectively evaluated for impairment	139,961	133,374
Commercial, Industrial and Agricultural Portfolio Segment [Member]
Construction loans:
Allowance for loan losses, beginning balance	531	319
Allowance for loan losses, recoveries		10
Allowance for loan losses, provisions	(102)	202
Allowance for loan losses, ending balance	429	531
Allowance for loan losses, ending balance: collectively evaluated for impairment	429	531
Loans	52,913	53,012
Loans,ending balance: individually evaluated for impairment	12	12
Loans, ending balance: collectively evaluated for impairment	52,901	53,000
Equity Lines Portfolio Segment [Member]
Construction loans:
Allowance for loan losses, beginning balance	277	423
Allowance for loan losses, recoveries		1
Allowance for loan losses, provisions	19	(147)
Allowance for loan losses, ending balance	296	277
Allowance for loan losses, ending balance: collectively evaluated for impairment	296	277
Loans	26,954	26,376
Loans, ending balance: collectively evaluated for impairment	26,954	26,376
Consumer Portfolio Segment [Member]
Construction loans:
Allowance for loan losses, beginning balance	85	65
Allowance for loan losses, charge-offs	(15)	(80)
Allowance for loan losses, recoveries	4	34
Allowance for loan losses, provisions	23	66
Allowance for loan losses, ending balance	97	85
Allowance for loan losses, ending balance: collectively evaluated for impairment	97	85
Loans	7,430	7,531
Loans, ending balance: collectively evaluated for impairment	7,430	7,531
Unallocated Financing Receivables [Member]
Construction loans:
Allowance for loan losses, beginning balance	87	184
Allowance for loan losses, provisions	5	(97)
Allowance for loan losses, ending balance	92	87
Allowance for loan losses, ending balance: collectively evaluated for impairment	$ 92	$ 87

No definition available.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

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.

+ References

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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
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Amount of expense related to estimated loss from loan and lease transactions.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
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