Restructuring (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Feb. 28, 2013	Feb. 29, 2012	Aug. 31, 2012
Restructuring
Restructuring Reserve	$ 4,497,000		$ 4,497,000		3,366,000
Pretax employee-related restructuring costs	1,669,000	1,597,000	3,606,000	4,841,000
Restructuring charges paid			(2,514,000)
Accelerated depreciation	404,000	0	682,000	0
EMEA [Member]
Restructuring
Pretax employee-related restructuring costs	1,138,000	1,285,000	2,695,000	4,346,000
Americas [Member]
Restructuring
Pretax employee-related restructuring costs	517,000	312,000	731,000	495,000
APAC [Member]
Restructuring
Pretax employee-related restructuring costs	14,000	0	180,000	0
Employee Related Costs [Member]
Restructuring
Restructuring Reserve	4,554,000		4,554,000		3,524,000
Pretax employee-related restructuring costs			3,194,000
Restructuring charges paid			(2,164,000)
Other Restructuring Related Costs [Member]
Restructuring
Restructuring Reserve	443,000		443,000		381,000
Pretax employee-related restructuring costs			412,000
Restructuring charges paid			(350,000)
Translation Effect on Restructuring Reserve [Member]
Restructuring
Restructuring Reserve	(500,000)		(500,000)		(539,000)
Brazil Consolidation Plan [Member]
Restructuring
Restructuring Reserve	300,000		300,000
Pretax employee-related restructuring costs	300,000
Pretax employee-related restructuring costs, expected costs			1,200,000
Restructuring And Related Cost Expected Accelerated Depreciation			300,000
Restructuring and Related Cost, Expected Number of Positions Eliminated			65
Restructuring Related Cost Number of Additional Positions			45
Accelerated depreciation	300,000
EMEA Continued Reorganization Plan [Member]
Restructuring
Restructuring Reserve	1,400,000		1,400,000
Pretax employee-related restructuring costs	1,000,000		2,400,000
Pretax employee-related restructuring costs, expected costs			300,000
Restructuring and Related Cost, Expected Number of Positions Eliminated			20
Bellevue, Ohio Facility Plan [Member]
Restructuring
Restructuring Reserve	100,000		100,000
Pretax employee-related restructuring costs	100,000		300,000
Pretax employee-related restructuring costs, expected costs			1,000,000
Accelerated depreciation	100,000		400,000
Masterbatch Reorganization Plan [Member]
Restructuring
Restructuring Reserve	2,000,000		2,000,000
EMEA Operations and Back-Office Plan [Member]
Restructuring
Restructuring Reserve	300,000		300,000
Pretax employee-related restructuring costs	0	1,200,000	300,000	3,900,000
Reduction in headcount					50
Americas Engineered Plastics Plan [Member]
Restructuring
Restructuring Reserve	200,000		200,000
Pretax employee-related restructuring costs		$ 300,000		$ 500,000
Reduction in headcount					70