Derivative Financial Instruments (Contractual and Weighted-Average Interest Rates, Which Include the Effects of Hedges Related to Financial Instruments) (Details) (Long-term debt)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Long-term debt
Derivative [Line Items]
Contractual Rates	3.40%	3.98%	3.57%	3.95%
Rate Including Impact of Hedges	2.65%	3.14%	2.83%	3.19%