Segment Reporting - Operating Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Net sales	$ 537,740	$ 449,987
Surfactants [Member]
Segment Reporting Information [Line Items]
Net sales	370,936	327,071
Polymers [Member]
Segment Reporting Information [Line Items]
Net sales	150,385	106,491
Specialty Products [Member]
Segment Reporting Information [Line Items]
Net sales	$ 16,419	$ 16,425

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details