Other Income, Net - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended						1 Months Ended	12 Months Ended		1 Months Ended				6 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Amalgamated Sugar Company LLC	Dec. 31, 2012 Amalgamated Sugar Company LLC	Dec. 31, 2011 Amalgamated Sugar Company LLC	Dec. 31, 2012 TIMET	Dec. 31, 2011 TIMET	Dec. 31, 2012 NL	May 31, 2012 NL Certain Real Property Litigation Settlement	Oct. 31, 2011 NL Certain Real Property Litigation Settlement	Apr. 30, 2009 NL Certain Real Property Litigation Settlement	Oct. 31, 2008 NL Certain Real Property Litigation Settlement	Jun. 30, 2012 NL Certain Real Property Litigation Settlement
Disclosure Other Income Net Additional Information Detail [Line Items]
Dividends and interest income	$ 26.4	$ 28.4	$ 29.2	$ 25.4	$ 25.4	$ 25.4
Investment in common stock								6.5
Percentage of outstanding common stock held								3.70%
Sale of common stock							107.6
Sale of common stock, price per share							$ 16.50
Pre-tax gain on sale of shares							21.6
Disposal of property and equipment, net	(0.5)	1.5	(0.9)						3.2
Promissory note received													15.0
Interest payable rate													2.75%
Aggregate cash received	0	15.6	0							15.6		11.8
Litigation settlement gains		14.7												14.7
Collection of real-estate related note receivable	$ 3.0	$ 0	$ 15.0								$ 15.0