Revenue from Contracts with Customers - Summary of Geographic Disaggregation of Net Sales (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Net sales	$ 537,740	$ 449,987
Surfactants [Member]
Disaggregation Of Revenue [Line Items]
Net sales	370,936	327,071
Polymers [Member]
Disaggregation Of Revenue [Line Items]
Net sales	150,385	106,491
Specialty Products [Member]
Disaggregation Of Revenue [Line Items]
Net sales	16,419	16,425
North America [Member]
Disaggregation Of Revenue [Line Items]
Net sales	305,750	283,281
North America [Member] | Surfactants [Member]
Disaggregation Of Revenue [Line Items]
Net sales	220,935	207,946
North America [Member] | Polymers [Member]
Disaggregation Of Revenue [Line Items]
Net sales	70,878	61,841
North America [Member] | Specialty Products [Member]
Disaggregation Of Revenue [Line Items]
Net sales	13,937	13,494
Europe [Member]
Disaggregation Of Revenue [Line Items]
Net sales	141,876	99,151
Europe [Member] | Surfactants [Member]
Disaggregation Of Revenue [Line Items]
Net sales	71,094	59,660
Europe [Member] | Polymers [Member]
Disaggregation Of Revenue [Line Items]
Net sales	68,300	36,560
Europe [Member] | Specialty Products [Member]
Disaggregation Of Revenue [Line Items]
Net sales	2,482	2,931
Latin America [Member]
Disaggregation Of Revenue [Line Items]
Net sales	61,159	47,149
Latin America [Member] | Surfactants [Member]
Disaggregation Of Revenue [Line Items]
Net sales	60,169	46,510
Latin America [Member] | Polymers [Member]
Disaggregation Of Revenue [Line Items]
Net sales	990	639
Asia [Member]
Disaggregation Of Revenue [Line Items]
Net sales	28,955	20,406
Asia [Member] | Surfactants [Member]
Disaggregation Of Revenue [Line Items]
Net sales	18,738	12,955
Asia [Member] | Polymers [Member]
Disaggregation Of Revenue [Line Items]
Net sales	$ 10,217	$ 7,451