Note 2 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Selling Costs, Percentage			10.00%
Impaired Financing Receivable, Related Allowance	$ 240		$ 240		$ 2,981
Other Real Estate	754		754		754
Other Real Estate, Gross	2,217		2,217		2,217
Real Estate Owned, Valuation Allowance	1,463		1,463		1,463
SEC Schedule III, Real Estate, Write-down or Reserve, Amount	0	$ 0	0	$ 0
Collateral Dependent Loans [Member]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	2,838		2,838		8,732
Impaired Financing Receivable, Related Allowance	142		142		2,913
Provision for Loan Losses Expensed	$ 142	$ 819	142	2,477	2,509
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down			$ 0	$ 0	$ 0