Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Dec. 31, 2015
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	$ 0		$ 0		$ 0	$ 0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Individually evaluated for impairment					15,000	6,000
Collectively evaluated for impairment					367,000	521,000
Ending balance	382,000	$ 634,000	382,000	$ 584,000	382,000	527,000
Beginning balance	408,000	634,000	527,000	609,000
Provision for Loan and Lease Losses	(29,000)	(15,000)	(70,000)	27,000
Charge-offs	(14,000)	(41,000)	(108,000)	(61,000)
Recoveries	17,000	6,000	33,000	9,000
Ending balance	382,000	584,000	382,000	584,000
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Individually evaluated for impairment					0	0
Collectively evaluated for impairment					49,000	157,000
Ending balance	49,000	173,000	49,000	161,000	49,000	157,000
Beginning balance	47,000	173,000	157,000	201,000
Provision for Loan and Lease Losses	2,000	(12,000)	(99,000)	(40,000)
Charge-offs	0	0	(9,000)	0
Recoveries	0	0	0	0
Ending balance	49,000	161,000	49,000	161,000
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Individually evaluated for impairment					0	0
Collectively evaluated for impairment					63,000	47,000
Ending balance	63,000	51,000	63,000	49,000	63,000	47,000
Beginning balance	42,000	51,000	47,000	60,000
Provision for Loan and Lease Losses	21,000	(2,000)	16,000	(11,000)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	63,000	49,000	63,000	49,000
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Individually evaluated for impairment					0	49,000
Collectively evaluated for impairment					1,576,000	1,492,000
Ending balance	1,576,000	1,669,000	1,576,000	1,613,000	1,576,000	1,541,000
Beginning balance	1,473,000	1,669,000	1,541,000	1,501,000
Provision for Loan and Lease Losses	100,000	(60,000)	96,000	96,000
Charge-offs	0	0	(82,000)	0
Recoveries	3,000	4,000	21,000	16,000
Ending balance	1,576,000	1,613,000	1,576,000	1,613,000
Commercial Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Commercial Portfolio Segment [Member]
Individually evaluated for impairment					0	100,000
Collectively evaluated for impairment					141,000	161,000
Ending balance	141,000	161,000	141,000	185,000	141,000	261,000
Beginning balance	162,000	161,000	261,000	1,480,000
Provision for Loan and Lease Losses	(21,000)	19,000	(9,000)	(97,000)
Charge-offs	0	0	(114,000)	(1,205,000)
Recoveries	0	5,000	3,000	7,000
Ending balance	141,000	185,000	141,000	185,000
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Individually evaluated for impairment					13,000	11,000
Collectively evaluated for impairment					813,000	615,000
Ending balance	826,000	648,000	826,000	644,000	826,000	626,000
Beginning balance	791,000	648,000	626,000	720,000
Provision for Loan and Lease Losses	31,000	26,000	223,000	(20,000)
Charge-offs	0	(36,000)	(36,000)	(68,000)
Recoveries	4,000	6,000	13,000	12,000
Ending balance	826,000	644,000	826,000	644,000
Consumer Portfolio Segment [Member] | Other Consumer Loan [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Consumer Portfolio Segment [Member] | Other Consumer Loan [Member]
Individually evaluated for impairment					6,000	0
Collectively evaluated for impairment					277,000	256,000
Ending balance	283,000	264,000	283,000	258,000	283,000	256,000
Beginning balance	266,000	264,000	256,000	275,000
Provision for Loan and Lease Losses	96,000	44,000	268,000	95,000
Charge-offs	(106,000)	(79,000)	(325,000)	(203,000)
Recoveries	27,000	29,000	84,000	91,000
Ending balance	283,000	258,000	283,000	258,000
Receivables Acquired with Deteriorated Credit Quality [Member]
Ending balance	0		0		0	0
Beginning balance			0
Ending balance	0		0
Individually evaluated for impairment					34,000	166,000
Collectively evaluated for impairment					3,286,000	3,249,000
Ending balance	3,320,000	3,600,000	3,320,000	3,494,000	$ 3,320,000	$ 3,415,000
Beginning balance	3,189,000	3,600,000	3,415,000	4,846,000
Provision for Loan and Lease Losses	200,000	0	425,000	50,000
Charge-offs	(120,000)	(156,000)	(674,000)	(1,537,000)
Recoveries	51,000	50,000	154,000	135,000
Ending balance	$ 3,320,000	$ 3,494,000	$ 3,320,000	$ 3,494,000