Aggregate Cash and Cash Equivalents (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 24, 2015	Jul. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 11,358	$ 12,241
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Market Value	11,358us-gaap_AvailableForSaleSecurities	12,241us-gaap_AvailableForSaleSecurities
Cash and cash equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,358	12,241
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Market Value	$ 11,358	$ 12,241

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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