Segment Reporting - Reconciliation of Segment Information to Income Before Provision for Income Taxes (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Operating Income		$ 20,169	$ 21,057
Business restructuring			(157)
Other Income (Expense)
Interest, net		(3,071)	(2,822)
Other, net		2,362	1,668
Income before provision for income taxes		19,460	19,903
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income		38,729	39,590
Operating Segments [Member] | Surfactants [Member]
Segment Reporting Information [Line Items]
Operating Income		26,079	27,056
Operating Segments [Member] | Polymers [Member]
Segment Reporting Information [Line Items]
Operating Income		8,382	10,004
Operating Segments [Member] | Specialty Products [Member]
Segment Reporting Information [Line Items]
Operating Income		4,268	2,530
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Unallocated corporate expenses	[1]	$ (18,560)	$ (18,376)

[1] Unallocated corporate expenses are primarily comprised of corporate administrative expenses (e.g., corporate finance, legal, human resources, information systems, deferred compensation and environmental remediation) that are not included in segment operating income and are not used to evaluate segment performance.