Condensed Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Feb. 29, 2012	Feb. 28, 2011	Feb. 29, 2012	Feb. 28, 2011
Distribution sales	$ 27,114	$ 24,694	$ 53,264	$ 50,038
Cost of goods sold	19,846	18,227	38,780	36,856
Gross profit from distribution operations	7,268	6,467	14,484	13,182
Rental revenue	312	311	623	623
Cost of rental operations	100	107	293	282
Gross profit from rental operations	212	204	330	341
Operating expenses:
Selling, general and administrative expenses	6,850	5,891	13,324	11,919
Total operating expenses	6,850	5,891	13,324	11,919
Income from operations	630	780	1,490	1,604
Non-operating income (expense):
Gain on sale of trading securities	62	247	62	253
Unrealized gain (loss) on trading securities	92	(69)	285	140
Interest expense, net	(178)	(190)	(359)	(385)
Total non-operating income (expense)	(24)	(12)	(12)	8
Net income before income taxes	606	768	1,478	1,612
Provision for income taxes	203	235	450	479
Net income	403	533	1,028	1,133
Undeclared cumulative preferred stock dividend	(19)	(19)	(38)	(38)
Net income attributable to common shareholders	$ 384	$ 514	$ 990	$ 1,095
Basic and diluted earnings per share (in dollars per share)	$ 0.08	$ 0.11	$ 0.20	$ 0.23
Basic and diluted weighted average common shares outstanding (in shares)	4,861,590	4,861,590	4,861,590	4,861,590