Note 13 - Stock Option Plans (Tables)

12 Months Ended

Dec. 31, 2015

Exercisable [Member]

Notes Tables

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Options Exercisable:
Range of Exercise Price				Number Exercisable		Wgt. Avg. Contractual Life Remaining (years)		Wgt. Avg. Exercise Price		Aggregate Intrinsic Value
$	0.69	-	$2.08		230,500		5.6	$	1.53	$	337,985
$	2.97	-	$3.84		24,000		1.9	$	3.57	$	54,960
$	0.69	-	$3.84		254,500		5.3	$	1.72	$	392,945

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	201 5				201 4
Options outstanding at January 1			274,500				270,500
Options cancelled			(8,000	)			(12,000	)
Options exercised			(4,000	)			--
Options granted			12,000				16,000
Options outstanding at December 31			274,500				274,500
Options available for grant at December 31			876,000				138,000
Options exercisable at December 31			254,500				250,000
Exercise price ranges per share:
Granted	$		2.97		$		1.35
Exercised	$		2.08				--
Outstanding	$0.69	-	$3.84		$0.69	-	$3.84
Weighted average exercise price per share:
Granted	$		2.97		$		1.35
Exercised	$		2.08				--
Outstanding at December 31	$		1.76		$		1.72
Exercisable at December 31	$		1.72		$		1.76

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Options Outstanding:
Range of  Exercise Price				Number Outstanding		Wgt. Avg. Contractual Life Remaining (years)		Wgt. Avg. Exercise Price		Aggregate Intrinsic Value
$	0.69	-	$2.08		238,500		5.7	$	1.52	$	356,145
$	2.97	-	$3.84		36,000		4.4	$	3.37	$	54,960
$	0.69	-	$3.84		274,500		5.5	$	1.76	$	411,105