Goodwill and Other Intangible Assets - Schedule of Changes in Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 14,732	$ 14,969
Accumulated impairment loss, Beginning Balance	(3,467)	(3,467)
Goodwill net, Beginning Balance	11,265	11,502
Goodwill acquired	14,327
Foreign currency translation	(284)	(237)
Goodwill, Ending Balance	28,775	14,732
Accumulated impairment loss, Ending Balance	(3,467)	(3,467)
Goodwill net, Ending Balance	25,308	11,265
Surfactants Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	8,869	9,025
Accumulated impairment loss, Beginning Balance	(3,467)	(3,467)
Goodwill net, Beginning Balance	5,402	5,558
Goodwill acquired	14,327
Foreign currency translation	(238)	(156)
Goodwill, Ending Balance	22,958	8,869
Accumulated impairment loss, Ending Balance	(3,467)	(3,467)
Goodwill net, Ending Balance	19,491	5,402
Polymer Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	5,380	5,461
Goodwill net, Beginning Balance	5,380	5,461
Foreign currency translation	(46)	(81)
Goodwill, Ending Balance	5,334	5,380
Goodwill net, Ending Balance	5,334	5,380
Specialty Products Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	483	483
Goodwill net, Beginning Balance	483	483
Goodwill, Ending Balance	483	483
Goodwill net, Ending Balance	$ 483	$ 483