Note 14 - Shareholder Rights Plan (Details Textual) - $ / shares	Jun. 18, 2009	Jun. 17, 2009	Dec. 31, 2018
Number of Series Junior Participating Preferred Stock Shares Reserved			150,000
Dividend Distribution Under Shareholder Rights Plan			1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right			0.01
Purchase Price Under Rights			$ 83
Acquisition Percentage			15.00%
Value of Exercised Right			2
Right Redemption Value			$ 0.01
Amended and Restated Rights Agreement Expiration Date	Jun. 28, 2019	Jun. 28, 2009