Fair Value Measures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Feb. 29, 2020		Aug. 31, 2019
Assets:
Nonqualified savings plan investments	$ 31,766		$ 27,967
Fair Value, Measurements, Recurring
Assets:
Derivative financial instruments	527		64
Nonqualified savings plan investments	31,766		27,967
Cash equivalents	23,166		68,100
Assets, Fair Value Disclosure, Total	55,459		96,131
Liabilities:
Derivative financial instruments	12,979		11,279
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Assets:
Nonqualified savings plan investments	31,766		27,967
Cash equivalents	23,166		68,100
Assets, Fair Value Disclosure, Total	54,932		96,067
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Assets:
Derivative financial instruments	527	[1]	64
Assets, Fair Value Disclosure, Total	527	[1]	64
Liabilities:
Derivative financial instruments	12,979	[1]	$ 11,279
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Liabilities:
Derivative financial instruments	$ 0

[1] Level 2 assets and liabilities include derivative financial instruments that are valued based on observable inputs. See Note 12 - Derivative Instruments for further discussion.