SEGMENT INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011 segment	Dec. 31, 2010	Dec. 31, 2009
Segment information
Number of reportable segments									3
Segment information
Net sales									$ 3,222,884	$ 2,818,040	$ 1,990,091
Total net sales	673,601	929,636	831,711	787,936	692,842	758,042	735,706	631,450	3,222,884	2,818,040	1,990,091
Long-lived asset impairment charges									8,318		21,804
Restructuring costs									3,271	102	6,858
(Gain) loss on sale of assets									(1,150)		62
Operating income	(1,967)	54,415	35,510	36,641	33,624	53,226	37,894	(10,474)	124,599	114,269	(568)
Depreciation and amortization									101,522	99,691	117,690
Capital expenditures									66,382	45,714	30,085
Total assets	1,644,211				1,665,701				1,644,211	1,665,701	1,604,640
Chlorovinyls
Segment information
Net sales									1,318,678	1,224,724	940,639
Intersegment revenues									235,683	245,977	198,996
Total net sales									1,554,361	1,470,701	1,139,635
Long-lived asset impairment charges											201
Restructuring costs									521	(340)	(19)
(Gain) loss on sale of assets									(1,150)
Operating income									143,304	114,297	79,469
Depreciation and amortization									56,014	59,524	60,362
Capital expenditures									37,059	22,810	21,553
Total assets	874,646				953,756				874,646	953,756	895,375
Aromatics
Segment information
Net sales									1,020,307	799,676	321,305
Total net sales									1,020,307	799,676	321,305
Operating income									10,370	23,335	16,884
Depreciation and amortization									1,483	1,405	4,297
Capital expenditures									1,637	2,641	188
Total assets	121,331				140,941				121,331	140,941	78,201
Building Products
Segment information
Net sales									883,899	793,639	728,147
Intersegment revenues									3	140	1,509
Total net sales									883,902	793,779	729,656
Long-lived asset impairment charges									8,318		21,603
Restructuring costs									2,750	442	4,409
(Gain) loss on sale of assets											62
Operating income									7,500	14,554	(26,713)
Depreciation and amortization									39,658	33,695	37,846
Capital expenditures									23,843	20,263	8,343
Total assets	606,442				554,016				606,442	554,016	537,515
Unallocated and Other
Segment information
Intersegment revenues									(235,686)	(246,117)	(200,505)
Total net sales									(235,686)	(246,117)	(200,505)
Restructuring costs											2,468
Operating income									(36,575)	(37,917)	(70,208)
Depreciation and amortization									4,367	5,067	15,185
Capital expenditures									3,843
Total assets	$ 41,792				$ 16,988				$ 41,792	$ 16,988	$ 93,549