Note 16 - Segment Information - Summary of Geographic Area Data (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Net sales to external customers		$ 35,055,315	$ 36,115,741
Assets by area		15,306,996	16,353,865
UNITED STATES
Net sales to external customers		25,747,158	27,673,352
Assets by area		12,340,835	13,584,424
Australia, New Zealand [Member]
Net sales to external customers		595,349	732,227
Assets by area		502,812	540,591
CANADA
Net sales to external customers		616,556	718,560
Assets by area		154,825	166,533
MEXICO
Net sales to external customers		577,488	474,372
Assets by area		223,238	179,713
Europe [Member]
Net sales to external customers	[1]	3,224,971	3,972,381
Assets by area	[1]	971,159	867,008
Asia [Member]
Net sales to external customers	[2]	4,293,793	2,544,849
Assets by area	[2]	$ 1,114,127	$ 1,015,596

[1] Europe consists of United Kingdom, Ireland, France, Germany, Austria, and the Netherlands.

[2] Asia consists of Philippines and Malaysia.