SEGMENT INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 segment	Mar. 31, 2011
Segment information
Number of reportable segments	3
Segment information
Net sales	$ 859,929	$ 787,936
(Gain) on sale of assets, restructuring expense and other, net	(12,449)	582
Operating income (loss)	68,255	36,641
Depreciation and amortization	22,603	25,449
Chlorovinyls
Segment information
Net sales	329,512	326,319
Intersegment revenues	67,648	64,261
(Gain) on sale of assets, restructuring expense and other, net	(17,386)	635
Operating income (loss)	51,917	37,740
Depreciation and amortization	11,108	14,599
Aromatics
Segment information
Net sales	343,177	304,113
Operating income (loss)	37,557	19,782
Depreciation and amortization	383	360
Building Products
Segment information
Net sales	187,240	157,504
Intersegment revenues	177	3
(Gain) on sale of assets, restructuring expense and other, net	(248)	(53)
Operating income (loss)	(6,426)	(12,066)
Depreciation and amortization	9,995	9,359
Unallocated and Other
Segment information
Intersegment revenues	(67,825)	(64,264)
(Gain) on sale of assets, restructuring expense and other, net	5,185
Operating income (loss)	(14,793)	(8,815)
Depreciation and amortization	$ 1,117	$ 1,131