Fair Value of Financial Instruments (Schedule of Pre-tax (Gain) Loss Recognized as a Component of Other Comprehensive Income) (Details) (Cash Flow Hedging [Member], Interest Rate Swap [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Cash Flow Hedging [Member] | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pre-Tax (Gain) Loss Recognized in OCI on Derivatives (Effective Portion)	$ (19)	$ 6	$ (22)	$ 4