Intangibles and Other Assets, Net - Identifiable Intangible and Other Assets (Detail) - USD ($) $ in Thousands	Nov. 30, 2018	Aug. 31, 2018
Intangibles and Other Assets by Major Class [Line Items]
Finite-Lived Intangible Assets, Net, Total	$ 36,696	$ 38,845
Intangible assets not subject to amortization	4,970	5,115
Prepaid and other assets	20,018	18,935
Nonqualified savings plan investments	26,992	26,299
Revolving notes issuance costs, net	3,632	1,824
Assets held for sale	3,650	3,650
Total Intangible and other assets, net	95,958	94,668
Customer Relationships
Intangibles and Other Assets by Major Class [Line Items]
Finite lived intangible assets gross	72,625	72,521
Accumulated amortization	(44,687)	(43,576)
Other Intangible Assets
Intangibles and Other Assets by Major Class [Line Items]
Finite lived intangible assets gross	15,925	16,300
Accumulated amortization	$ (7,167)	$ (6,400)