Earnings Per Share (Details) In Thousands, unless otherwise specified	3 Months Ended
Oct. 31, 2012	Oct. 31, 2011
Weighted-average number of shares used in the calculation of basic and diluted earnings per share
Weighted-average number of shares used in calculation of basic earnings per share	20,807	20,365
Effect of dilutive securities:
Stock options
Non-vested restricted Class B common stock	1,277
Weighted-average number of shares used in calculation of diluted earnings per share	22,084	20,365

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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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