Segment Information (Major Customers) (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Customer A [Member]
Revenue, Major Customer [Line Items]
Revenue from major customers as percentage of consolidated revenue	15.60%	13.10%	11.50%
Customer B [Member]
Revenue, Major Customer [Line Items]
Revenue from major customers as percentage of consolidated revenue	10.00%
Customer C [Member]
Revenue, Major Customer [Line Items]
Revenue from major customers as percentage of consolidated revenue		10.80%
Customer Concentration Risk [Member] | Sales Revenue, Net [Member] | Chemicals and Logistics [Member] | Major Customers [Member]
Revenue, Major Customer [Line Items]
Revenue from major customers within segments	95.00%