Note 3 - Loans and Allowance for Loan Losses - Activity for Troubled Debt Restructurings (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Beginning Balance	$ 1,503,000	$ 2,028,000
Charge-Offs	0	0
Payments	(125,000)	(101,000)
Transfers to ORE	0	0
Net Additions/Deletions	159,000	19,000
Ending Balance	1,537,000	1,946,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Beginning Balance	1,488,000	2,086,000
Charge-Offs	0	0
Payments	(529,000)	(24,000)
Transfers to ORE	0	0
Net Additions/Deletions	0	0
Ending Balance	959,000	2,062,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member]
Beginning Balance	906,000	1,400,000
Charge-Offs	0	0
Payments	(27,000)	(31,000)
Transfers to ORE	0	0
Net Additions/Deletions	0	0
Ending Balance	879,000	1,369,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Beginning Balance	5,110,000	10,657,000
Charge-Offs	0	0
Payments	(123,000)	(128,000)
Transfers to ORE	0	0
Net Additions/Deletions	(436,000)	0
Ending Balance	4,551,000	10,529,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Beginning Balance	716,000	476,000
Charge-Offs	0	0
Payments	(113,000)	(7,000)
Transfers to ORE	0	0
Net Additions/Deletions	(312,000)	0
Ending Balance	291,000	469,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Beginning Balance	1,125,000	1,686,000
Charge-Offs	0	(48,000)
Payments	(233,000)	0
Transfers to ORE	0	0
Net Additions/Deletions	30,000	49,000
Ending Balance	922,000	1,687,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Beginning Balance	0	0
Charge-Offs	0	0
Payments	0	0
Transfers to ORE	0	0
Net Additions/Deletions	0	0
Ending Balance	0	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member]
Beginning Balance	900,000	1,652,000
Charge-Offs	(12,000)	0
Payments	0	(197,000)
Transfers to ORE	0	0
Net Additions/Deletions	108,000	0
Ending Balance	996,000	1,455,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Beginning Balance	728,000	647,000
Charge-Offs	0	0
Payments	(145,000)	(10,000)
Transfers to ORE	0	0
Net Additions/Deletions	0	0
Ending Balance	583,000	637,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Beginning Balance	60,000	331,000
Charge-Offs	0	0
Payments	0	(53,000)
Transfers to ORE	0	0
Net Additions/Deletions	8,000	0
Ending Balance	68,000	278,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Beginning Balance	385,000	146,000
Charge-Offs	0	0
Payments	0	0
Transfers to ORE	0	0
Net Additions/Deletions	321,000	0
Ending Balance	706,000	146,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member]
Beginning Balance	157,000	128,000
Charge-Offs	0	0
Payments	(3,000)	(2,000)
Transfers to ORE	0	0
Net Additions/Deletions	0	0
Ending Balance	154,000	126,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Beginning Balance	208,000	141,000
Charge-Offs	0	0
Payments	(9,000)	(6,000)
Transfers to ORE	0	0
Net Additions/Deletions	7,000	26,000
Ending Balance	206,000	161,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member]
Beginning Balance	326,000	316,000
Charge-Offs	0	0
Payments	(4,000)	0
Transfers to ORE	0	0
Net Additions/Deletions	54,000	19,000
Ending Balance	$ 376,000	$ 335,000