Goodwill and Other Intangible Assets - Components of Other Intangible Assets and Changes in Gross Carrying Values (Detail) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value		$ 37,530	$ 31,897
Other Finite-Lived Intangible Assets, Accumulated Amortization		22,178	17,653
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value		6,947	6,947
Other Finite-Lived Intangible Assets, Accumulated Amortization		5,091	4,492
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value		374	387
Other Finite-Lived Intangible Assets, Accumulated Amortization		242	173
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value		4,087	3,800
Other Finite-Lived Intangible Assets, Accumulated Amortization		2,561	1,929
Customer Lists/relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value	[1]	14,539	10,750
Other Finite-Lived Intangible Assets, Accumulated Amortization	[1]	5,983	4,356
Know-how [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value	[1],[2]	9,543	7,900
Other Finite-Lived Intangible Assets, Accumulated Amortization	[1],[2]	6,644	5,514
Supply Contract [Member]
Finite-Lived Intangible Assets [Line Items]
Other Finite-Lived Intangible Assets, Gross Carrying Value		2,040	2,113
Other Finite-Lived Intangible Assets, Accumulated Amortization		$ 1,657	$ 1,189

[1] In 2019, customer lists/relationships and know- how include the acquisition of an oilfield demulsifier product line.  See Note 21 for more details.

[2] Know-how includes intellectual property rights covering proprietary information, written formulae, trade secrets or secret processes, inventions and developmental products (whether patentable or not), discoveries, improvements, compositions, manufacturing processes, manuals, specifications and technical data