Commitments and Contingencies (Details Textual) (USD $)	1 Months Ended		5 Months Ended	12 Months Ended
	Oct. 13, 2010 County	May 31, 2007 Company	Jun. 06, 2008 Well	Dec. 31, 2011 Entity Agreement Complaint	Dec. 31, 2010	Dec. 31, 2009 Insurer	May 18, 2010	Dec. 31, 2008
Commitments and Contingencies (Textual)
Expenditures under the noncapital purchase commitments				$ 89,407,000	$ 111,142,000	$ 99,838,000
Commitments of minimum royalties under mineral leases				215,043,000
Expenditures for mineral royalties under mineral leases				45,690,000	43,111,000	43,501,000
Number of wells at issue			244
Number of wells at issue as a result of the discovery to date			14
Period of letters of credit				1 year
Amount of bank credit facility				600,000,000
Number of earn-out agreements in connection with the sale of the Chemicals business				2
Transaction bonuses paid				1,228,000
Unrecognized tax benefits				13,488,000	28,075,000	20,974,000		18,131,000
Number of cases in mass tort action	over 100
Claims against damages, IDOT/Joliet Road lawsuit							40,000,000
Payment to Illinois Department of Transportation (IDOT)				20,000,000
Settlement awarded				49,657,000
Number of other parties sued in the Lower Passaic River Clean-Up				300
Number of other companies to perform a Remedial Investigation/Feasibility Study related to the Lower Passaic River Clean-Up lawsuit		70
Number of counties that cases were filed in the mass tort action	17
Number of insurers						2
Complaints in Florida Antitrust Litigation				2
Range of estimated cost, minimum				900,000,000
Range of estimated cost, maximum				2,300,000,000
Property Plant And Equipment [Member]
Commitments and Contingencies (Textual)
Unconditional purchase obligations				3,745,000
Noncapital [Member]
Commitments and Contingencies (Textual)
Unconditional purchase obligations				$ 67,532,000