Note 13 - Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2014

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

	First		Second		Third		Fourth
2014	Quarter		Quarter		Quarter		Quarter
Net sales	$	19,838,466	$	19,703,607	$	19,417,234	$	24,471,605
Gross profit		12,715,723		12,779,606		12,174,709		14,454,719
Net income		1,854,412		1,765,485		1,628,562		2,458,462
Net income per common share:
Basic	$	0.18	$	0.17	$	0.16	$	0.24
Diluted	$	0.18	$	0.17	$	0.16	$	0.24
Weighted average number of common shares outstanding:
Basic		10,198,733		10,198,733		10,203,711		10,210,933
Diluted		10,239,505		10,239,823		10,241,410		10,244,127

	First		Second		Third		Fourth
2013	Quarter		Quarter		Quarter		Quarter
Net sales	$	19,237,827	$	18,973,013	$	18,524,604	$	21,549,141
Gross profit		11,930,829		11,920,121		11,700,943		13,776,131
Net income		1,586,321		1,629,353		1,561,832		2,488,211
Net income per common share:
Basic	$	0.16	$	0.16	$	0.15	$	0.24
Diluted	$	0.16	$	0.16	$	0.15	$	0.24
Weighted average number of common shares outstanding:
Basic		10,162,442		10,167,649		10,176,744		10,198,733
Diluted		10,194,219		10,216,535		10,221,512		10,233,009