Condensed Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Net sales	$ 184,449	$ 173,014	$ 548,085	$ 585,337
Cost of sales	102,517	98,186	307,163	327,021
Gross profit	81,932	74,828	240,922	258,316
Selling, general and administrative expenses	39,095	33,533	110,132	108,449
Engineering, research and development expenses	13,314	11,957	38,029	36,951
Amortization of intangible assets	2,389	2,505	7,259	7,763
Operating income	27,134	26,833	85,502	105,153
Interest income	(83)	(58)	(183)	(105)
Interest expense	43	20	171	755
Other expense, net	1,481	315	648	(1,643)
Income before income taxes and equity in net income of affiliates	25,693	26,556	84,866	106,146
Income tax expense	7,656	4,582	27,300	22,550
Equity in net income of affiliates		(14)	(3)	(489)
Net income	18,037	21,988	57,569	84,085
Less net income attributable to noncontrolling interest				400
Net income attributable to Entegris, Inc.	$ 18,037	$ 21,988	$ 57,569	$ 83,685
Amounts attributable to Entegris, Inc.:
Basic net income per common share	$ 0.13	$ 0.16	$ 0.42	$ 0.62
Diluted net income per common share	$ 0.13	$ 0.16	$ 0.42	$ 0.62
Weighted shares outstanding:
Basic	137,453	134,995	137,119	134,410
Diluted	138,499	136,305	138,247	135,954