Reconciliation of Segment Margin to Earnings Before Income Tax and Earnings from Unconsolidated Affiliates (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 28, 2016	Nov. 30, 2015	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015
Segment Reporting, Other Significant Reconciling Item [Line Items]
Earnings from operations	$ 57,780	$ 48,472	$ 81,520	$ 72,660	$ 83,545	$ 84,129	$ 92,393	$ 148,485	$ 260,432	$ 408,552	$ 386,892
Interest and foreign exchange	8,901	7,894	5,673	1,724	2,937	3,712	1,417	5,436	24,192	13,502	11,179
Earnings before income tax and earnings from unconsolidated affiliates	$ 48,879	$ 40,578	$ 75,847	$ 70,936	$ 80,608	$ 80,417	$ 90,976	$ 143,049	$ 236,240	$ 395,050	$ 375,713

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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