Stock-Based Compensation (Details 3) (USD $)			12 Months Ended
Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013 Range of Exercise Prices one	Jul. 31, 2013 Range of Exercise Prices two	Jul. 31, 2013 Range of Exercise Prices three	Jul. 31, 2013 Range of Exercise Prices four
Additional information related to stock options outstanding
Exercise price low end of range (in dollars per share)			$ 4.14	$ 6.28	$ 7.13	$ 4.14
Exercise price high end of range (in dollars per share)			$ 5.14	$ 7.06	$ 17.04	$ 17.04
Options Outstanding
Number Outstanding (in shares)			10,128	316,337	77,366	403,831
Weighted Average Remaining Contractual Life			3 months	16 months	40 months	20 months
Weighted Average Exercise Price (in dollars per share)			$ 4.26	$ 6.99	$ 13.93	$ 8.25
Total Intrinsic Value (in dollars)	$ 7,386,000	$ 8,925,000
Options Exercisable
Number Exercisable (in shares)			10,128	316,337	24,866	351,331
Weighted Average Remaining Contractual Life (in months)			3 months	16 months	16 months	16 months
Weighted Average Exercise Price (in dollars per share)			$ 4.26	$ 6.99	$ 7.38	$ 6.94
Total Intrinsic Value (in dollars)	$ 6,887,000

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