OTHER CURRENT AND NON-CURRENT ASSETS (Details 2) (USD $) In Thousands	Jul. 31, 2011	Jul. 31, 2010
Equity Securities Amortized Cost Basis	$ 2,381	$ 2,375
Cost/Amortized Cost Basis
Securities	77,448	66,288
Fair Value
Securities	91,056	73,529
Gross Unrealized Holding Gains
Securities	13,671	7,251
Gross Unrealized Holding Losses
Securities	(63)	(10)
Net Unrealized Holding Gains
Securities	13,608	7,241
Corporate Debt Securities [Member]
Cost/Amortized Cost Basis
Securities	36,608	25,769
Fair Value
Securities	38,505	27,676
Gross Unrealized Holding Gains
Securities	1,960	1,912
Gross Unrealized Holding Losses
Securities	(63)	(5)
Net Unrealized Holding Gains
Securities	1,897	1,907
U.S. Treasury [Member]
Cost/Amortized Cost Basis
Securities	9,544	17,905
Fair Value
Securities	10,210	19,209
Gross Unrealized Holding Gains
Securities	666	1,304
Gross Unrealized Holding Losses
Securities	0	0
Net Unrealized Holding Gains
Securities	666	1,304
Other U.S. government [Member]
Cost/Amortized Cost Basis
Securities	27,749	19,009
Fair Value
Securities	29,089	20,163
Gross Unrealized Holding Gains
Securities	1,340	1,159
Gross Unrealized Holding Losses
Securities	0	(5)
Net Unrealized Holding Gains
Securities	1,340	1,154
Municipal government [Member]
Cost/Amortized Cost Basis
Securities	1,000	1,000
Fair Value
Securities	1,002	1,001
Gross Unrealized Holding Gains
Securities	2	1
Gross Unrealized Holding Losses
Securities	0	0
Net Unrealized Holding Gains
Securities	2	1
CMO/mortgage-backed [Member]
Cost/Amortized Cost Basis
Securities	166	230
Fair Value
Securities	186	256
Gross Unrealized Holding Gains
Securities	20	26
Gross Unrealized Holding Losses
Securities	0	0
Net Unrealized Holding Gains
Securities	20	26
Equity Securities [Member]
Fair Value
Securities	12,064	5,224
Gross Unrealized Holding Gains
Securities	9,683	2,849
Gross Unrealized Holding Losses
Securities	0	0
Net Unrealized Holding Gains
Securities	$ 9,683	$ 2,849

Available For Sale Securities Debt Securities Fair Value.

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for 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 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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