Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jan. 31, 2013	Jan. 31, 2012
Condensed Consolidated Statements of Operations (Unaudited) [Abstract]
Loss from discontinued operations, net of income tax benefit	$ 0	$ (382)

Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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