Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
May 05, 2012 SecuritiesHold	Aug. 27, 2011
Available-for-sale marketable securities
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 76,218	$ 72,393
Available-For-Sale Marketable Securities, Gross Unrealized Gains	538	783
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(12)	(45)
Available-For-Sale Marketable Securities, Fair Value	76,744	73,131
Marketable Securities (Textual) [Abstract]
Available for sale securities debt maturity period range	Less than one year to approximately 3 years
Number of securities held in unrealized loss position	8
Available for sale securities in continuous unrealized loss position amount	(12)
Corporate securities [Member]
Available-for-sale marketable securities
Available-For-Sale Marketable Securities, Amortized Cost Basis	24,930	26,261
Available-For-Sale Marketable Securities, Gross Unrealized Gains	234	229
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(5)	(45)
Available-For-Sale Marketable Securities, Fair Value	25,159	26,445
Government bonds [Member]
Available-for-sale marketable securities
Available-For-Sale Marketable Securities, Amortized Cost Basis	27,792	29,464
Available-For-Sale Marketable Securities, Gross Unrealized Gains	184	343
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(3)	0
Available-For-Sale Marketable Securities, Fair Value	27,973	29,807
Mortgage-backed securities [Member]
Available-for-sale marketable securities
Available-For-Sale Marketable Securities, Amortized Cost Basis	4,868	4,291
Available-For-Sale Marketable Securities, Gross Unrealized Gains	26	55
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(4)	0
Available-For-Sale Marketable Securities, Fair Value	4,890	4,346
Asset-Backed securities and other [Member]
Available-for-sale marketable securities
Available-For-Sale Marketable Securities, Amortized Cost Basis	18,628	12,377
Available-For-Sale Marketable Securities, Gross Unrealized Gains	94	156
Available-For-Sale Marketable Securities, Gross Unrealized Losses	0	0
Available-For-Sale Marketable Securities, Fair Value	$ 18,722	$ 12,533

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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This item represents the excess of amortized cost basis over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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- Definition

Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired.

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