Note 13 - Shareholder Rights Plan (Details Textual) - Shareholder Rights Plan Two Thousand Eight [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Apr. 04, 2008
Exercise Price per Share	$ 75
Stock Redemption Price per Share	0.01
Series B Junior Participating Preferred Stock [Member]
Exercise Price per Share	175,000
Stock Redemption Price per Share	$ 0.01
Maximum [Member]
Stock Holders Rights Plan Exercisability Threshold Percentage		15.00%
Stockholder Rights Plan Exercise Trigger Threshold Percentage Voting Stock Ownership Offer		15.00%
Percentage of Beneficial Ownership Interests	50.00%