Description Of Business And Significant Accounting Policies (Schedule Of Estimated Useful Lives Of Assets) (Details)	12 Months Ended
	Dec. 31, 2011 years
Buildings And Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, maximum (in years)	25
Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, maximum (in years)	25
Ethylene Pipeline [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, maximum (in years)	35
Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	3
Property, plant and equipment, useful life, maximum (in years)	10