Condensed Consolidated Statements of Stockholders Equity (Parenthetical) (USD $)	3 Months Ended				9 Months Ended
	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Apr. 30, 2011	Apr. 30, 2012	Apr. 30, 2011
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share	$ 0.15	$ 0.15	$ 0.15	$ 0	$ 0.45	$ 0