Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended
Oct. 31, 2015	Oct. 31, 2014
Weighted-average number of shares used in the calculation of basic and diluted earnings per share
Basic weighted-average number of shares	22,935	22,755
Effect of dilutive securities:
Stock options		27
Non-vested restricted Class B common stock	34	309
Diluted weighted-average number of shares	22,969	23,091

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 23
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-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1757-109256

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6527216

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Nonvested equity-based payment awards that contain forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) that result in incremental common shares.

+ References

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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.

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