Stockholders' Equity (Summary Of Stock Option Activity) (Details) (USD $)	12 Months Ended
Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Stockholders' Equity Note [Abstract]
Outstanding, Shares, Beginning Balance	337,526	723,251
Granted	40,625	75,625
Exercised	$ 0	$ (84,372)
Cancelled	(29,688)	(376,978)
Outstanding, Shares, Ending Balace	348,463	337,526
Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 21.02	$ 17.01
Weighted Average Exercise Price, Granted	$ 6.68	$ 9.56
Weighted Average Exercise Price, Exercised	$ 0.00	$ 5.11
Weighted Average Exercise Price, Cancelled	$ 22.05	$ 14.58
Outstanding, Weighted Average Exercise Price, Ending Balance	$ 19.26	$ 21.02
Aggregate Intrinsic Value, Outstanding	$ 0	$ 30,000	$ 5,070,000

Stock Options Exercised

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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- Definition

Net number of share options (or share units) granted during the period.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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