Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Jan. 31, 2014	Jul. 31, 2013
Trade receivables, allowance for doubtful accounts	$ 377	$ 220
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	13,367,992	12,976,588
Common stock, shares outstanding	13,367,992	12,976,588
Cumulative Preferred Stock [Member]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Junior Preferred Stock [Member]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	100,000	100,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0