Acquisitions - Summary of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Mar. 26, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 03, 2016
Assets:
Goodwill	$ 22,954		$ 25,118	$ 25,308
2018 Acquisition [Member] | BASF Mexicana, S.A. DE C.V. [Member]
Assets:
Property, plant and equipment		$ 14,464
Inventory		5,687
Other Receivable		2,701
Total assets acquired		22,852
Property, plant and equipment		$ 14,464
2016 Acquisition [Member] | Tebras And PBC [Member]
Assets:
Property, plant and equipment					$ 5,716
Total assets acquired					32,442
Current assets					5,165
Property, plant and equipment					5,716
Identifiable intangible assets					7,354
Goodwill					14,207
Liabilities:
Current liabilities					408
Deferred tax liability					3,079
Total liabilities assumed					3,487
Net assets acquired					$ 28,955