Net Loss and Diluted Loss Per Common Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Net income (loss)	$ 3,929us-gaap_NetIncomeLoss	$ (1,604)us-gaap_NetIncomeLoss	$ 15,991us-gaap_NetIncomeLoss	$ (8,504)us-gaap_NetIncomeLoss
Basic EPS:
Weighted average shares outstanding- basic	54,362	48,220	52,745	48,060
Basic income (loss) per share	$ 0.07us-gaap_EarningsPerShareBasic	$ (0.03)us-gaap_EarningsPerShareBasic	$ 0.30us-gaap_EarningsPerShareBasic	$ (0.18)us-gaap_EarningsPerShareBasic
Diluted EPS:
Weighted average shares outstanding- basic	54,362	48,220	52,745	48,060
Plus: impact of stock options and unvested RSUs	305		765
Weighted average shares outstanding- diluted	54,667	48,220	53,510	48,060
Diluted income (loss) per share	$ 0.07us-gaap_EarningsPerShareDiluted	$ (0.03)us-gaap_EarningsPerShareDiluted	$ 0.30us-gaap_EarningsPerShareDiluted	$ (0.18)us-gaap_EarningsPerShareDiluted

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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