Derivative Financial Instruments (Schedule of Interest Rate Swap Activity Recorded in the Consolidated Financial Statements) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Hedging activities - Interest expense	$ (147)	$ (172)	$ (185)
Swap Derivative 1 Point 02 Percent Maturing January 2, 2016 [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Expiration Date		Jan. 02, 2016		Jan. 02, 2016
Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedging activities - Interest expense	(4)	(11)	(14)
Ineffective portion - Other income (expense), net	$ 0	$ 0	$ 0