Note 3 - Loans - Loans Individually Evaluated for Impairment (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Commercial and Industrial Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	$ 1,753,000	$ 3,119,000
Loans with no related allowance recorded, unpaid principal balance	2,321,000	3,859,000
Loans with no related allowance recorded, average recorded investment	2,805,000	1,414,000
Loans with an allowance recorded, recorded investment	998,000	1,516,000
Loans with an allowance recorded, unpaid principal balance	1,473,000	3,087,000
Related allowance	286,000	268,000
Loans with an allowance recorded, average recorded investment	1,206,000	4,612,000
Recorded investment	2,751,000	4,635,000
Unpaid principal balance	3,794,000	6,946,000
Average recorded investment	4,011,000	6,026,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	1,753,000	3,119,000
Loans with no related allowance recorded, unpaid principal balance	2,321,000	3,859,000
Loans with no related allowance recorded, average recorded investment	2,805,000	1,414,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	998,000	1,516,000
Loans with an allowance recorded, unpaid principal balance	1,473,000	3,087,000
Related allowance	286,000	268,000
Loans with an allowance recorded, average recorded investment	1,206,000	4,612,000
Total:
Recorded investment	2,751,000	4,635,000
Unpaid principal balance	3,794,000	6,946,000
Related allowance	286,000	268,000
Average recorded investment	4,011,000	6,026,000
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance		151,000
Loans with no related allowance recorded, average recorded investment		21,000
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		368,000
Recorded investment
Unpaid principal balance		151,000
Average recorded investment		389,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance		151,000
Loans with no related allowance recorded, average recorded investment		21,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		368,000
Total:
Recorded investment
Unpaid principal balance		151,000
Related allowance
Average recorded investment		389,000
Undevelopment Land Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance
Loans with no related allowance recorded, average recorded investment
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Recorded investment
Unpaid principal balance
Average recorded investment
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment
Loans with no related allowance recorded, unpaid principal balance
Loans with no related allowance recorded, average recorded investment
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Total:
Recorded investment
Unpaid principal balance
Related allowance
Average recorded investment
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans with no related allowance recorded, recorded investment	280,000	278,000
Loans with no related allowance recorded, unpaid principal balance	280,000	278,000
Loans with no related allowance recorded, average recorded investment	254,000	178,000
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		92,000
Recorded investment	280,000	278,000
Unpaid principal balance	280,000	278,000
Average recorded investment	254,000	270,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	280,000	278,000
Loans with no related allowance recorded, unpaid principal balance	280,000	278,000
Loans with no related allowance recorded, average recorded investment	254,000	178,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		92,000
Total:
Recorded investment	280,000	278,000
Unpaid principal balance	280,000	278,000
Related allowance
Average recorded investment	254,000	270,000
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans with no related allowance recorded, recorded investment	1,241,000	1,743,000
Loans with no related allowance recorded, unpaid principal balance	1,678,000	2,713,000
Loans with no related allowance recorded, average recorded investment	1,559,000	1,622,000
Loans with an allowance recorded, recorded investment	394,000	1,018,000
Loans with an allowance recorded, unpaid principal balance	394,000	1,018,000
Related allowance	7,000	208,000
Loans with an allowance recorded, average recorded investment	761,000	1,266,000
Recorded investment	1,635,000	2,761,000
Unpaid principal balance	2,072,000	3,731,000
Average recorded investment	2,320,000	2,888,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	1,241,000	1,743,000
Loans with no related allowance recorded, unpaid principal balance	1,678,000	2,713,000
Loans with no related allowance recorded, average recorded investment	1,559,000	1,622,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	394,000	1,018,000
Loans with an allowance recorded, unpaid principal balance	394,000	1,018,000
Related allowance	7,000	208,000
Loans with an allowance recorded, average recorded investment	761,000	1,266,000
Total:
Recorded investment	1,635,000	2,761,000
Unpaid principal balance	2,072,000	3,731,000
Related allowance	7,000	208,000
Average recorded investment	2,320,000	2,888,000
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans with no related allowance recorded, recorded investment	977,000	906,000
Loans with no related allowance recorded, unpaid principal balance	977,000	906,000
Loans with no related allowance recorded, average recorded investment	999,000	661,000
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		188,000
Recorded investment	977,000	906,000
Unpaid principal balance	977,000	906,000
Average recorded investment	999,000	849,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	977,000	906,000
Loans with no related allowance recorded, unpaid principal balance	977,000	906,000
Loans with no related allowance recorded, average recorded investment	999,000	661,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment		188,000
Total:
Recorded investment	977,000	906,000
Unpaid principal balance	977,000	906,000
Related allowance
Average recorded investment	999,000	849,000
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans with no related allowance recorded, recorded investment		13,000
Loans with no related allowance recorded, unpaid principal balance		13,000
Loans with no related allowance recorded, average recorded investment	4,000	37,000
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Recorded investment		13,000
Unpaid principal balance		13,000
Average recorded investment	4,000	37,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment		13,000
Loans with no related allowance recorded, unpaid principal balance		13,000
Loans with no related allowance recorded, average recorded investment	4,000	37,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Total:
Recorded investment		13,000
Unpaid principal balance		13,000
Related allowance
Average recorded investment	4,000	37,000
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans with no related allowance recorded, recorded investment	253,000	92,000
Loans with no related allowance recorded, unpaid principal balance	253,000	92,000
Loans with no related allowance recorded, average recorded investment	211,000	69,000
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Recorded investment	253,000	92,000
Unpaid principal balance	253,000	92,000
Average recorded investment	211,000	69,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	253,000	92,000
Loans with no related allowance recorded, unpaid principal balance	253,000	92,000
Loans with no related allowance recorded, average recorded investment	211,000	69,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment
Loans with an allowance recorded, unpaid principal balance
Related allowance
Loans with an allowance recorded, average recorded investment
Total:
Recorded investment	253,000	92,000
Unpaid principal balance	253,000	92,000
Related allowance
Average recorded investment	211,000	69,000
Real Estate Mortgage Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	2,751,000	3,032,000
Loans with no related allowance recorded, unpaid principal balance	3,188,000	4,002,000
Loans with no related allowance recorded, average recorded investment	3,027,000	2,567,000
Loans with an allowance recorded, recorded investment	394,000	1,018,000
Loans with an allowance recorded, unpaid principal balance	394,000	1,018,000
Related allowance	7,000	208,000
Loans with an allowance recorded, average recorded investment	761,000	1,546,000
Recorded investment	3,145,000	4,050,000
Unpaid principal balance	3,582,000	5,020,000
Average recorded investment	3,788,000	4,113,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	2,751,000	3,032,000
Loans with no related allowance recorded, unpaid principal balance	3,188,000	4,002,000
Loans with no related allowance recorded, average recorded investment	3,027,000	2,567,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	394,000	1,018,000
Loans with an allowance recorded, unpaid principal balance	394,000	1,018,000
Related allowance	7,000	208,000
Loans with an allowance recorded, average recorded investment	761,000	1,546,000
Total:
Recorded investment	3,145,000	4,050,000
Unpaid principal balance	3,582,000	5,020,000
Related allowance	7,000	208,000
Average recorded investment	3,788,000	4,113,000
Consumer Portfolio Segment [Member]
Loans with no related allowance recorded, recorded investment	31,000
Loans with no related allowance recorded, unpaid principal balance	31,000
Loans with no related allowance recorded, average recorded investment	21,000	3,000
Loans with an allowance recorded, recorded investment	63,000	68,000
Loans with an allowance recorded, unpaid principal balance	63,000	68,000
Related allowance	63,000	68,000
Loans with an allowance recorded, average recorded investment	66,000	72,000
Recorded investment	94,000	68,000
Unpaid principal balance	94,000	68,000
Average recorded investment	87,000	75,000
Loans with no related allowance recorded:
Loans with no related allowance recorded, recorded investment	31,000
Loans with no related allowance recorded, unpaid principal balance	31,000
Loans with no related allowance recorded, average recorded investment	21,000	3,000
Loans with an allowance recorded:
Loans with an allowance recorded, recorded investment	63,000	68,000
Loans with an allowance recorded, unpaid principal balance	63,000	68,000
Related allowance	63,000	68,000
Loans with an allowance recorded, average recorded investment	66,000	72,000
Total:
Recorded investment	94,000	68,000
Unpaid principal balance	94,000	68,000
Related allowance	63,000	68,000
Average recorded investment	87,000	75,000
Loans with no related allowance recorded, recorded investment	4,535,000	6,151,000
Loans with no related allowance recorded, unpaid principal balance	5,540,000	8,012,000
Loans with no related allowance recorded, average recorded investment	5,853,000	4,005,000
Loans with an allowance recorded, recorded investment	1,455,000	2,602,000
Loans with an allowance recorded, unpaid principal balance	1,930,000	4,173,000
Related allowance	356,000	544,000
Loans with an allowance recorded, average recorded investment	2,033,000	6,598,000
Recorded investment	5,990,000	8,753,000
Unpaid principal balance	7,470,000	12,185,000
Average recorded investment	7,886,000	10,603,000
Loans with no related allowance recorded, recorded investment	4,535,000	6,151,000
Loans with no related allowance recorded, unpaid principal balance	5,540,000	8,012,000
Loans with no related allowance recorded, average recorded investment	5,853,000	4,005,000
Loans with an allowance recorded, recorded investment	1,455,000	2,602,000
Loans with an allowance recorded, unpaid principal balance	1,930,000	4,173,000
Related allowance	356,000	544,000
Loans with an allowance recorded, average recorded investment	2,033,000	6,598,000
Recorded investment	5,990,000	8,753,000
Unpaid principal balance	7,470,000	12,185,000
Related allowance	356,000	544,000
Average recorded investment	$ 7,886,000	$ 10,603,000