Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Income Statement [Abstract]
Net sales	$ 7,891,877	$ 7,993,927
Cost of sales	5,409,684	5,992,119
Gross profit	2,482,193	2,001,808
Selling, general and administrative expenses	722,589	742,867
Operating income	1,759,604	1,258,941
Other income
Interest and dividend income	10,905	10,167
Other	4,849	26,883
Total other income	15,754	37,050
Income before income taxes	1,775,358	1,295,991
Provision for income taxes	494,640	369,087
Net income	1,280,718	926,904
Other comprehensive income, net of tax:
Unrealized gain (loss) on investment securities	283	(1,692)
Total other comprehensive income	$ 283	$ (1,692)
Net income per share:
Basic	$ 0.59	$ 0.43
Diluted	$ 0.57	$ 0.42
Weighted average number of shares outstanding:
Basic	2,186,424	2,164,202
Diluted	2,234,361	2,196,104
Dividends per share:	$ 0.225	$ 0.225