Note 13 - Stock Option Plans - Stock Options Outstanding (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 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)	$ 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)	$ 593,970
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)	$ 3.89
Number Outstanding (in Shares) (in shares)	78,000
Wgt. Avg. Contractual Life Remaining (yrs) (Year)	6 years 292 days
Wgt. Avg. Exercise Price (in dollars per share)	$ 3.59
Aggregate Intrinsic Value (in Dollars)	$ 68,880
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)	$ 3.89
Number Outstanding (in Shares) (in shares)	304,500
Wgt. Avg. Contractual Life Remaining (yrs) (Year)	5 years 109 days
Wgt. Avg. Exercise Price (in dollars per share)	$ 2.06
Aggregate Intrinsic Value (in Dollars)	$ 662,850