Note 4 - Trading Account Assets (Details) - Components of Trading Account Assets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total trading account assets	$ 10,090	$ 5,513
Trading, Municipal Bonds [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Municipal bonds	8,148	4,116
Trading, Insured Bank Deposits [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Insured bank deposits	$ 1,942	$ 1,397