Note 13 - Stock Options Outstanding (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Options Outstanding Exercise Price Range1 [Member]
Lower range of exercise price (in dollars per share)	$ 0.69
Upper range of exercise price (in dollars per share)	$ 2.08
Number outstanding (in shares) | shares	238,500
Wgt. avg. contractual life remaining (yrs)	5 years 255 days
Outstanding at December 31 (in dollars per share)	$ 1.52
Aggregate intrinsic value | $	$ 356,145
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
Number outstanding (in shares) | shares	36,000
Wgt. avg. contractual life remaining (yrs)	4 years 146 days
Outstanding at December 31 (in dollars per share)	$ 3.37
Aggregate intrinsic value | $	$ 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
Number outstanding (in shares) | shares	274,500
Wgt. avg. contractual life remaining (yrs)	5 years 182 days
Outstanding at December 31 (in dollars per share)	$ 1.76
Aggregate intrinsic value | $	$ 411,105
Number outstanding (in shares) | shares	274,500
Outstanding at December 31 (in dollars per share)	$ 1.76