Statements of Comprehensive Income - USD ($)	12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Statements of Comprehensive Income [Abstract]
Net sales	$ 26,831,705	$ 27,136,919
Cost of sales	19,690,132	22,605,673
Gross profit	7,141,573	4,531,246
Selling, general and administrative expenses	2,711,807	3,214,050
Operating income	4,429,766	1,317,196
Other income
Interest income	36,424	40,612
Other	31,626	108,141
Total other income	68,050	148,753
Income before income taxes	4,497,816	1,465,949
Provision for income taxes	1,314,689	298,064
Net income	3,183,127	1,167,885
Other comprehensive income, net of tax:
Unrealized loss on investment securities	(2,949)	(1,849)
Total comprehensive income	$ 3,180,178	$ 1,166,036
Net income per share:
Basic	$ 1.40	$ 0.52
Diluted	$ 1.39	$ 0.51
Weighted average number of shares outstanding:
Basic	2,271,426	2,245,222
Diluted	2,290,542	2,285,535