Note 2 - Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2015

Notes Tables

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

Risk-free interest rate	1.45%	-	1.64%
Expected volatility	83%	-	102%
Dividend yield		0%
Expected option term (years)		5

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Options			Weighted average e xercise price		Weighted average remaining contractual term (in years)		Aggregate i ntrinsic value
Outstanding
at beginning of period		349,983		$	10.97
Exercised		(55,000	)		8.00
Outstanding and vested
at end of period		294,983		$	11.53		1.82	$	146,598