Note 2 - Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2017

Notes Tables

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

	201 7				201 6
Dividend yield (1)			0.0%				0.0%
Expected volatility (2)		45.50%	to	50.09%		47.59%	to	52.54%
Risk-free interest rate (3)		1.89%	to	2.26%		1.23%	to	1.82%
Expected life (4) (in years)		5.5	to	7.0		5.5	to	7.0
Assumed forfeiture rate (5)			6.0%				10.0%

Share-based Compensation, Activity [Table Text Block]

	201 7		201 6
Stock based compensation expense recognized	$	302,000	$	171,000
Number of unvested stock options		1,697,852		1,254,226
Fair value of unvested stock options	$	4,583,209	$	2,418,303
Amount remaining to be recognized as expense	$	3,935,014	$	1,690,057

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months Ended March 31,
	2017		2016
Net income - basic and diluted	$	1,787	$	1,085
Weighted average shares outstanding		56,824		37,837
Net income per share – basic	$	0.03	$	0.03
Weighted average shares outstanding (including dilutive CSEs)		58,048		38,269
Net income per share – diluted	$	0.03	$	0.03

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Three Months Ended March 31,
(in thousands)	2017		2016
Anti-dilutive securities
Share based compensation awards		1,897		2,059
Convertible securities		1,625		1,662
Total anti-dilutive securities		3,522		3,721