Note 7 - Income Taxes - Deferred Income Tax Assets and Liabilities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Capitalized inventory costs	$ 179,535	$ 198,616
Warrants and share-based compensation	29,047	29,047
Accrued expenses, reserves, and other	39,646	44,075
Total deferred income tax assets	248,228	271,738
Deferred income tax liabilities:
Property and equipment depreciation	889,719	1,008,485
Goodwill and other intangible assets amortization	159,435	155,175
Transition tax on deemed repatriation of foreign earnings	507,339	473,298
Total deferred income tax liabilities	$ 1,556,493	$ 1,636,958