Net Income Per Share (Details)	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Earnings Per Share [Abstract]
Weighted average common shares outstanding (in shares)	75,649,000	84,165,000	83,537,000
Effect of dilutive securities-stock options (in shares)	1,027	862	1,393
Diluted weighted average common shares outstanding (in shares)	76,676,000	85,027,000	84,930,000
Dilutive earnings per share to Purchase of common stock outstanding (in shares)	2,553,989	5,892,641	1,225,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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+ Details