Offsetting Assets and Liabilities (Assets) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Derivatives:
Gross Amounts of Recognized Assets	$ 3,263		$ 3,261
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	(2,919)	[1]	(3,154)	[1]
Cash Collateral	(145)		(18)
Securities Collateral	(114)		(16)
Net Amount	85		73
OTC derivatives
Derivatives:
Gross Amounts of Recognized Assets	3,090		3,180
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	(2,837)	[1]	(3,134)	[1]
Cash Collateral	(121)		(17)
Securities Collateral	(114)		(16)
Net Amount	18		13
Over the Counter Cleared Swaps [Member]
Derivatives:
Gross Amounts of Recognized Assets	106		21
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	(82)	[1]	(20)	[1]
Cash Collateral	(24)		(1)
Net Amount	0		0
Exchange-traded derivatives
Derivatives:
Gross Amounts of Recognized Assets	67		60
Gross Amounts Not Offset in the Consolidated Balance Sheets
Net Amount	$ 67		$ 60

[1] Represents the amount of assets that could be offset by liabilities with the same counterparty under master netting or similar arrangements that management elects not to offset on the Consolidated Balance Sheets.