Commitments, Contingencies and Legal Proceedings (Details) (USD $)	1 Months Ended	9 Months Ended
	Feb. 28, 2011	Sep. 30, 2012 Municipality Defendant EnforcementAction OperableUnit	Mar. 19, 2012 sqyd	Oct. 14, 2010 Party
Commitments Contingencies and Legal Proceedings (Textual) [Abstract]
Number of operable units		5
Number of principal enforcement actions		3
Number of parties against action is filed				12
Cost of response incurred by government		$ 17,000,000
Area of segment for dredging			660,000
Number of Defendants de minimis in the Whiting Litigation settled		13
Number of municipalities		2
Estimated cost of remediation made by government to all parties		1,000,000,000
Reasonable outside estimate for cost of remediation made by government to all parties		1,500,000,000
Initial minimum amount of NRD assessment		176,000,000
Initial maximum amount of NRD assessment		333,000,000
Findings of fact and conclusions of law subject to an unresolved insurance coverage settlement		4,250,000
Revised minimum amount of NRD assessment		287,000,000
Revised maximum amount of NRD assessment		423,000,000
The limitation period for the NRD's claims		3 years
Percentage of cost of response reimbursable	100.00%
Reserve for claiming liability		16,500,000
Reserve for environmental liability, current portion		300,000
Maximum estimated percentage of discharge		27.00%
Maximum estimated cost related to Fox River Matter		$ 265,000,000
Period over which estimated cost accrued		10 years