Note 9 - Quarterly Results for 2013 and 2014 (Unaudited) (Details) - Quarterly Results (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Quarterly Results [Abstract]
Net sales	$ 49,701,000	$ 52,291,000	$ 53,230,000	$ 41,027,000	$ 45,473,000	$ 44,184,000	$ 30,854,000	$ 30,985,000
Gross profit	17,242,000	18,433,000	19,006,000	14,056,000	15,027,000	15,040,000	11,178,000	11,313,000	68,737,000	52,558,000
Income before taxes on income	4,616,000	5,168,000	5,867,000	1,878,000	2,545,000	2,128,000	2,068,000	1,749,000
Net income	$ 2,856,000	$ 3,368,000	$ 3,907,000	$ 1,218,000	$ 1,675,000	$ 1,508,000	$ 1,438,000	$ 1,229,000	$ 11,349,000	$ 5,850,000
Basic
Net income (in Dollars per share)	$ 0.21	$ 0.25	$ 0.30	$ 0.09	$ 0.13	$ 0.12	$ 0.12	$ 0.10	$ 0.85	$ 0.47
Diluted
Net income (in Dollars per share)	$ 0.20	$ 0.24	$ 0.29	$ 0.09	$ 0.13	$ 0.12	$ 0.12	$ 0.10	$ 0.82	$ 0.46
Average Outstanding Shares (Basic) (in Shares)	13,481,494	13,375,566	13,207,804	13,128,946	12,905,174	12,692,520	12,252,646	12,242,360	13,298,452	12,523,176
Average Outstanding Shares (Diluted) (in Shares)	14,252,310	14,004,202	13,648,540	13,553,740	13,261,852	12,807,786	12,340,242	12,338,950	13,864,698	12,687,208