Segment Reporting - Summary of Segment Depreciation and Amortization (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Summary of segment depreciation and amortization
Depreciation	$ 3.5	$ 3.3	$ 6.6	$ 6.5
Amortization	6.1	5.3	12.1	10.4
Operating Segments [Member] | Fuel Specialties [Member]
Summary of segment depreciation and amortization
Depreciation	1.0	0.8	1.9	1.6
Amortization	0.3	0.3	0.5	0.5
Operating Segments [Member] | Performance Chemicals [Member]
Summary of segment depreciation and amortization
Depreciation	0.6	0.6	1.1	1.2
Amortization	1.0	1.0	2.0	2.0
Operating Segments [Member] | Oilfield Services [Member]
Summary of segment depreciation and amortization
Depreciation	1.5	1.4	2.9	2.7
Amortization	3.0	3.0	6.0	6.0
Operating Segments [Member] | Octane Additives [Member]
Summary of segment depreciation and amortization
Depreciation	0.2	0.1	0.3	0.2
Corporate, Non-Segment [Member]
Summary of segment depreciation and amortization
Depreciation	0.2	0.4	0.4	0.8
Amortization	$ 1.8	$ 1.0	$ 3.6	$ 1.9