Note 13 - Stock Options Exercisable (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Options Exercisable Exercise Price Range 1 [Member]
Lower range of exercise price (in dollars per share)	$ 0.69
Upper range of exercise price (in dollars per share)	$ 2.08
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	230,500
Wgt. avg. contractual life remaining (years)	5 years 219 days
Exercisable at December 31 (in dollars per share)	$ 1.53
Aggregate intrinsic value - exercisable | $	$ 337,985
Options Outstanding Exercise Price Range2 [Member]
Lower range of exercise price (in dollars per share)	$ 2.97
Upper range of exercise price (in dollars per share)	$ 3.84
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	24,000
Wgt. avg. contractual life remaining (years)	1 year 328 days
Exercisable at December 31 (in dollars per share)	$ 3.57
Aggregate intrinsic value - exercisable | $	$ 54,960
Options Outstanding Exercise Price Range 3 [Member]
Lower range of exercise price (in dollars per share)	$ 0.69
Upper range of exercise price (in dollars per share)	$ 3.84
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	254,500
Wgt. avg. contractual life remaining (years)	5 years 109 days
Exercisable at December 31 (in dollars per share)	$ 1.72
Aggregate intrinsic value - exercisable | $	$ 392,945
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | shares	254,500
Exercisable at December 31 (in dollars per share)	$ 1.72