Quarterly Financial Information (Unaudited) (Schedule of Quarterly Financial Information) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 12,124,438	$ 6,191,300	$ 7,286,674	$ 5,923,819	$ 11,619,202	$ 9,218,141	$ 7,303,109	$ 8,337,399	$ 31,526,231	$ 36,477,851
Gross profit	2,031,186	910,933	1,480,148	1,136,348	2,403,565	2,150,439	1,516,235	992,934	5,558,615	7,063,173
Net income (loss)	$ 956,693	$ (103,765)	$ 228,964	$ 81,776	$ 1,140,809	$ 922,456	$ 217,758	$ 61,671	$ 1,163,668	$ 2,342,694
Net income (loss) per share -
Basic	$ 0.40	$ (0.04)	$ 0.10	$ 0.03	$ 0.48	$ 0.39	$ 0.09	$ 0.03	$ 0.49	$ 0.99
Diluted	$ 0.40	$ (0.04)	$ 0.10	$ 0.03	$ 0.47	$ 0.39	$ 0.09	$ 0.03	$ 0.49	$ 0.98