Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2015	Jul. 31, 2014
Allowance for doubtful accounts	$ 365	$ 348
Preferred stock, shares authorized	1,000,000us-gaap_PreferredStockSharesAuthorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	250,000,000us-gaap_CommonStockSharesAuthorized	250,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	62,301,037us-gaap_CommonStockSharesIssued	62,210,429us-gaap_CommonStockSharesIssued
Treasury, shares	8,911,474us-gaap_TreasuryStockShares	8,880,877us-gaap_TreasuryStockShares

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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