Short-term and Long-term Investments (Details 1) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2014
Legal maturities of debt investments
Amortized Cost, Less than one year	$ 120,208
Amortized Cost, Due in 1-2 years	65,043
Amortized Cost, Total	185,251
Estimated Fair Value, Less than one year	120,250
Estimated Fair Value, Due in 1-2 years	65,019
Estimated Fair Value	$ 185,269

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

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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