Note 13 - Stock Option Plans - Stock Options Exercisable (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number Outstanding (in Shares) (in shares)	304,500	274,500	274,500
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)	$ 1.72
Number Outstanding (in Shares) (in shares)	226,500
Wgt. Avg. Contractual Life Remaining (yrs) (Year)	4 years 292 days
Wgt. Avg. Exercise Price (in dollars per share)	$ 1.54
Aggregate Intrinsic Value (in Dollars)	$ 566,970
Options Exercisable Exercise Price Range 2 [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) (in shares)	30,000
Wgt. Avg. Contractual Life Remaining (yrs) (Year)	2 years 146 days
Wgt. Avg. Exercise Price (in dollars per share)	$ 3.45
Aggregate Intrinsic Value (in Dollars)	$ 68,880
Options Exercisable Exercise Price Range3 [Member]
Lower Range of Exercise Price (in dollars per share)	$ 0.69
Upper Range of Exercise Price (in dollars per share)	$ 384
Number Outstanding (in Shares) (in shares)	256,500
Wgt. Avg. Contractual Life Remaining (yrs) (Year)	4 years 182 days
Wgt. Avg. Exercise Price (in dollars per share)	$ 1.76
Aggregate Intrinsic Value (in Dollars)	$ 635,850