Segment Information - Reconciliation of Earnings from Operations to Earnings Before Income Tax and Earnings (Loss) from Unconsolidated Affiliates (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017
Segment Reporting, Other Significant Reconciling Item [Line Items]
Earnings from operations	$ 60,870	$ 81,520	$ 122,312	$ 154,180
Interest and foreign exchange	7,029	5,673	14,049	7,397
Earnings before income tax and earnings (loss) from unconsolidated affiliates	$ 53,841	$ 75,847	$ 108,263	$ 146,783

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Period Type:	duration