Segment Reporting - Summary of Segment Depreciation and Amortization (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Summary of segment depreciation and amortization
Depreciation	$ 6.1	$ 5.7
Amortization	5.8	5.7
Operating Segments [Member] | Fuel Specialties [Member]
Summary of segment depreciation and amortization
Depreciation	1.0	0.9
Operating Segments [Member] | Performance Chemicals [Member]
Summary of segment depreciation and amortization
Depreciation	2.8	2.5
Amortization	2.2	2.2
Operating Segments [Member] | Oilfield Services [Member]
Summary of segment depreciation and amortization
Depreciation	1.7	1.7
Amortization	2.6	2.6
Operating Segments [Member] | Octane Additives [Member]
Summary of segment depreciation and amortization
Depreciation	0.3	0.3
Corporate, Non-Segment [Member]
Summary of segment depreciation and amortization
Depreciation	0.3	0.3
Amortization	$ 1.0	$ 0.9