Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Number of contracts		4	6	5
Pre-modification outstanding principal balance		$ 3,042	$ 3,628	$ 5,761
Post-modification outstanding principal balance	[1]	$ 3,043	$ 3,541	$ 5,843
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Number of contracts		2		2
Pre-modification outstanding principal balance		$ 3,008		$ 2,967
Post-modification outstanding principal balance	[1]	$ 3,008		$ 3,008
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Number of contracts			3	1
Pre-modification outstanding principal balance			$ 2,710	$ 184
Post-modification outstanding principal balance	[1]		$ 2,623	$ 208
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member]
Number of contracts				1
Pre-modification outstanding principal balance				$ 2,484
Post-modification outstanding principal balance	[1]			$ 2,484
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member]
Number of contracts			2
Pre-modification outstanding principal balance			$ 718
Post-modification outstanding principal balance	[1]		$ 718
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member]
Number of contracts				1
Pre-modification outstanding principal balance				$ 126
Post-modification outstanding principal balance	[1]			$ 143
Commercial Non Real Estate Segment [Member]
Number of contracts		1
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member]
Number of contracts		1	1
Pre-modification outstanding principal balance		$ 29	$ 200
Post-modification outstanding principal balance	[1]	$ 30	$ 200
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member]
Number of contracts		1
Pre-modification outstanding principal balance		$ 5
Post-modification outstanding principal balance	[1]	$ 5

[1] Post-modification outstanding recorded investment considers amounts immediately following the modification. Amounts do not reflect balances at the end of the period.