Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jul. 31, 2013	Jul. 31, 2012
Allowance for doubtful accounts	$ 157	$ 527
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	62,045,264	61,777,849
Treasury, shares	8,858,280	8,857,339

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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