Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Aug. 31, 2012	May 31, 2012	Feb. 29, 2012	Nov. 30, 2011	Aug. 31, 2011	May 31, 2011	Feb. 28, 2011	Nov. 30, 2010	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers	$ 524,446	$ 569,107	$ 495,911	$ 517,289	$ 578,087	$ 611,142	$ 508,343	$ 495,383	$ 2,106,753	$ 2,192,955	$ 1,590,443
Segment gross profit									278,094	286,153	236,879
Asset write-downs									0	0	(69)
Inventory step-up									(677)	(607)	(3,942)
Gross profit	66,783	76,589	64,549	69,496	71,045	78,888	66,612	69,001	277,417	285,546	232,868
Segment operating income									110,866	106,282	84,410
Costs related to acquisitions									(1,425)	(1,429)	(6,814)
Restructuring related									(9,256)	(8,117)	(5,098)
Asset write-downs									(3,392)	(8,150)	(5,737)
Curtailment gain (loss)									310	0	(270)
Operating income									72,640	62,873	42,055
Operating income											42,011
Interest expense, net									(7,678)	(5,531)	(3,665)
Foreign currency transaction gains (losses)									(245)	(1,595)	(884)
Other income (expense), net									1,251	1,720	2,425
Other income (expense), net											2,469
Income from continuing operations before taxes									65,968	57,467	39,931
Identifiable assets	1,193,767				1,239,987				1,193,767	1,239,987	1,071,315
Depreciation and amortization expense									38,784	40,274	27,449
Capital expenditures									34,003	26,359	18,977
Long lived assets	225,876				234,300				225,876	234,300	238,963
Net sales, percentage	100.00%				100.00%				100.00%	100.00%	100.00%
Masterbatch [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									876,126	880,406	676,977
Net sales, percentage	42.00%				40.00%				42.00%	40.00%	43.00%
Engineered Plastics [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									547,090	546,964	460,141
Net sales, percentage	26.00%				25.00%				26.00%	25.00%	29.00%
Specialty Powders [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									340,446	372,360	129,122
Net sales, percentage	16.00%				17.00%				16.00%	17.00%	8.00%
Distribution Services [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									343,091	393,225	324,203
Net sales, percentage	16.00%				18.00%				16.00%	18.00%	20.00%
France [Member]
Segment Reporting Information [Line Items]
Long lived assets	22,832				21,744				22,832	21,744	19,536
Germany [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									571,876	617,266	496,073
Long lived assets	23,020				27,680				23,020	27,680	24,876
United States [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									358,376	337,423	231,890
Long lived assets	76,699				74,102				76,699	74,102	89,345
Other International [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									1,176,501	1,238,266	862,480
Long lived assets	103,325				110,774				103,325	110,774	105,206
EMEA [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									1,403,151	1,533,993	1,142,523
Segment gross profit									171,768	197,171	177,010
Segment operating income									71,849	86,663	69,393
Identifiable assets	677,066				737,698				677,066	737,698	616,592
Depreciation and amortization expense									17,534	18,522	13,896
Capital expenditures									11,383	12,541	10,927
Americas [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									558,910	516,814	363,011
Segment gross profit									84,282	71,698	48,213
Segment operating income									28,872	14,032	12,036
Identifiable assets	426,963				408,714				426,963	408,714	369,210
Depreciation and amortization expense									17,531	17,810	11,144
Capital expenditures									17,725	12,328	7,125
APAC [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers									144,692	142,148	84,909
Segment gross profit									22,044	17,284	11,656
Segment operating income									10,145	5,587	2,981
Identifiable assets	89,738				93,575				89,738	93,575	85,513
Depreciation and amortization expense									3,719	3,942	2,409
Capital expenditures									4,895	1,490	925
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Segment operating income									$ (23,786)	$ (25,106)	$ (20,538)