Components of Income Tax Expense of Continuing Operations (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
Current
Federal									$ 22,710	$ 66,455	$ 92,525
State									305	4,595	6,349
Foreign									35,893	50,299	32,748
Current Income Tax Expense (Benefit), Total									58,908	121,349	131,622
Deferred
Federal									9,418	(6,199)	(13,565)
State									(1,467)	(1,174)	(1,112)
Foreign									(2,732)	(1,644)	(4,423)
Total Deferred Income Tax Expense (Benefit)									5,219	(9,017)	(19,100)
Change in valuation allowance									(113)	(10)	(362)
Income tax expense	$ 10,114	$ 8,656	$ 24,858	$ 20,386	$ 19,420	$ 22,449	$ 25,734	$ 44,719	$ 64,014	$ 112,322	$ 112,160