Fair Value Measures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Aug. 31, 2018	Aug. 31, 2017
Assets:
Nonqualified savings plan investments	$ 26,299	$ 20,974
Fair Value, Measurements, Recurring
Assets:
Derivative financial instruments	1,557	3,814
Nonqualified savings plan investments	26,299	20,974
Cash equivalents	126,430	105,337
Assets, Fair Value Disclosure, Total	154,286	130,125
Liabilities:
Derivative financial instruments	1,566	2,886
Fair Value, Inputs, Level 1 \| Fair Value, Measurements, Recurring
Assets:
Nonqualified savings plan investments	26,299	20,974
Cash equivalents	126,430	105,337
Assets, Fair Value Disclosure, Total	152,729	126,311
Fair Value, Inputs, Level 2 \| Fair Value, Measurements, Recurring
Assets:
Derivative financial instruments	1,557	3,814
Assets, Fair Value Disclosure, Total	1,557	3,814
Liabilities:
Derivative financial instruments	$ 1,566	$ 2,886

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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