Changes in Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Feb. 28, 2015	Aug. 31, 2015	Aug. 31, 2014
Goodwill [Roll Forward]
Beginning Balance		$ 742,770	$ 734,952
Recognition of Goodwill due to Business acquired			17,536
Purchase accounting adjustments		(3,244)	(835)
Goodwill, Impairment Charge	$ (78,000)	(78,530)
Write off of goodwill related to a business divestiture			(17,843)
Impact of changes in foreign currency rates		(52,740)	8,960
Ending Balance		608,256	742,770
Industrial
Goodwill [Roll Forward]
Beginning Balance		100,266	82,611
Recognition of Goodwill due to Business acquired			17,536
Purchase accounting adjustments		(3,244)	0
Goodwill, Impairment Charge		0
Write off of goodwill related to a business divestiture			0
Impact of changes in foreign currency rates		(4,915)	119
Ending Balance		92,107	100,266
Energy
Goodwill [Roll Forward]
Beginning Balance		350,627	341,903
Recognition of Goodwill due to Business acquired			0
Purchase accounting adjustments		0	(835)
Goodwill, Impairment Charge		(78,530)
Write off of goodwill related to a business divestiture			0
Impact of changes in foreign currency rates		(35,647)	9,559
Ending Balance		236,450	350,627
Engineered Solutions
Goodwill [Roll Forward]
Beginning Balance		291,877	310,438
Recognition of Goodwill due to Business acquired			0
Purchase accounting adjustments		0	0
Goodwill, Impairment Charge		0
Write off of goodwill related to a business divestiture			(17,843)
Impact of changes in foreign currency rates		(12,178)	(718)
Ending Balance		$ 279,699	$ 291,877