Accounting Policies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Line Items]
Non-cash pension expense, net of tax		$ 1.4	$ 1.8	$ 16.1
Impairment of goodwill	1.3	1.2	2.0
Minimum [Member]
Accounting Policies [Line Items]
Short-term investments maturity period	3 months
Maximum [Member]
Accounting Policies [Line Items]
Cash equivalents maturity period	3 months
Short-term investments maturity period	12 months
Fuel Specialties [Member]
Accounting Policies [Line Items]
Impairment of goodwill	0	0
Performance Chemicals [Member]
Accounting Policies [Line Items]
Impairment of goodwill	$ 0	$ 0