Changes in Goodwill by Operating Segment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 273,145	$ 272,238
Acquisitions		3,672	[1]
Foreign currency translation adjustments	3,821	(2,765)
Goodwill, Ending Balance	276,966	273,145
Polymer Solutions
Goodwill [Line Items]
Goodwill, Beginning Balance	37,163	36,210
Foreign currency translation adjustments	452	953
Goodwill, Ending Balance	37,615	37,163
Catalysts
Goodwill [Line Items]
Goodwill, Beginning Balance	211,210	211,423
Acquisitions		3,672	[1]
Foreign currency translation adjustments	3,361	(3,885)
Goodwill, Ending Balance	214,571	211,210
Fine Chemistry
Goodwill [Line Items]
Goodwill, Beginning Balance	24,772	24,605
Foreign currency translation adjustments	8	167
Goodwill, Ending Balance	$ 24,780	$ 24,772

[1] Relates to our acquisition of Catilin, Inc. as discussed in Note 22 "Acquisitions."