Derivative Instruments (Textuals) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Parent [Member]	Dec. 31, 2013 Parent [Member]	Mar. 31, 2014 Noncontrolling Interest [Member]	Dec. 31, 2013 Noncontrolling Interest [Member]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax	$ 0	$ 1
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax			148	148	11	11
Derivative Instruments (Textuals) [Abstract]
Maximum length of time hedging using interest rate derivative instruments	10 years
Derivative, Net Liability Position, Aggregate Fair Value	58
Collateral Already Posted, Aggregate Fair Value	7
Additional Collateral, Aggregate Fair Value	1
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	5
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 43