Balance Sheet Information - Summary of Estimated Fair Value of Investments in Marketable Debt Securities (Detail) $ in Thousands	Aug. 31, 2017 USD ($)
Balance Sheet Information [Abstract]
Due in 1 year	$ 21,434
Due in 1 year through 5 years	52,893
Due in 5 years through 10 years	3,020
Due after 10 years	3,644
Total	$ 80,991

Balance Sheet Information [Abstract]

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- Definition

Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

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