Business Segment Information - Segment Operating Performance (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Net sales	$ 516.0	$ 568.3	$ 1,015.2	$ 1,151.1
Cost of sales	498.8	406.3	985.1	728.7
Gross margin	17.2	162.0	30.1	422.4
Operating income (loss)	(46.8)	103.2	(92.0)	306.5
Equity in earnings of investees	(0.5)	(0.1)	(0.8)
Securities earnings	6.7	7.1	13.3	14.2
Insurance recoveries	1.0	0.3	1.6	1.4
Litigation settlement gain		14.7		14.7
Loss on prepayment of debt		(7.2)	(6.6)	(7.2)
General expenses, net	(21.6)	(9.2)	(31.3)	(29.5)
Interest expense	(14.7)	(14.3)	(30.1)	(27.8)
Income (loss) from continuing operations before income taxes	(75.9)	94.5	(145.9)	272.3
Chemicals
Segment Reporting Information [Line Items]
Net sales	481.1	545.3	944.7	1,106.6
Cost of sales	472.1	382.6	932.4	683.0
Gross margin	9.0	162.7	12.3	423.6
Operating income (loss)	(45.3)	112.4	(90.4)	323.7
Component Products
Segment Reporting Information [Line Items]
Net sales	24.0	22.1	45.5	42.5
Cost of sales	16.4	15.6	31.9	30.0
Gross margin	7.6	6.5	13.6	12.5
Operating income (loss)	2.9	2.1	4.4	3.7
Waste Management
Segment Reporting Information [Line Items]
Net sales	10.9	0.9	25.0	2.0
Cost of sales	10.3	8.1	20.8	15.7
Gross margin	0.6	(7.2)	4.2	(13.7)
Operating income (loss)	$ (4.4)	$ (11.3)	$ (6.0)	$ (20.9)