Note 7 - Segment Information (Details) - Net sales for geographic areas were as follows: (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations	$ 18,973,013	$ 16,904,254	$ 38,210,840	$ 35,081,332
United States [Member] | Three Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			15,741,570	14,112,191
United States [Member] | Six Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			31,937,964	29,639,646
Canada [Member] | Three Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			1,918,986	1,732,982
Canada [Member] | Six Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			3,838,709	3,452,822
All Other Countries [Member] | Three Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			1,312,457	1,059,081
All Other Countries [Member] | Six Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			2,434,167	1,988,864
Three Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			18,973,013	16,904,254
Six Months [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Geographic locations			$ 38,210,840	$ 35,081,332