Condensed Consolidated Statements of Income (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jan. 31, 2012	Jan. 31, 2011
Condensed Consolidated Statements of Income [Abstract]
Loss from discontinued operations, income tax benefit	$ 193	$ (2)

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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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details