Derivative Financial Instruments (Contractual And Weighted-Average Interest Rates, Which Include The Effects Of Hedges Related To Financial Instruments) (Details) (Long-Term Debt [Member])	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Long-Term Debt [Member]
Derivative [Line Items]
Contractual Rates	3.64%	3.70%
Rate Including Impact of Hedges	3.22%	3.30%