Derivative Instruments And Hedging Activities (Fair Value Amounts Of Derivative Instruments Reported On Our Condensed Consolidated Balance Sheet) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 263,000,000	$ 362,000,000
Derivative Liability, Fair Value, Gross Liability	252,000,000	317,000,000
Derivative, Notional Amount	81,200,000,000invest_DerivativeNotionalAmount	101,221,000,000invest_DerivativeNotionalAmount
Accrued Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	50,000,000	120,000,000
Derivative Liability, Fair Value, Gross Liability	17,000,000	12,000,000
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	118,000,000	207,000,000
Derivative Liability, Fair Value, Gross Liability	7,000,000	169,000,000
Derivative, Notional Amount	18,764,000,000	21,932,000,000
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	118,000,000	204,000,000
Derivative Liability, Fair Value, Gross Liability	7,000,000	169,000,000
Derivative, Notional Amount	18,554,000,000	21,606,000,000
Hedge notional amount associated with debt maturing in five or more years	2,700,000,000
Foreign Exchange Forward [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	3,000,000
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative, Notional Amount	210,000,000	326,000,000
Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Receive-fixed Swaps, Fair Value, Gross Asset	97,000,000	196,000,000
Receive-fixed Swaps, Fair Value, Gross Liability	1,000,000	163,000,000
Receive-fixed Swaps, Notional Amount	4,700,000,000	8,500,000,000
Pay-fixed Swaps, Fair Value, Gross Asset	21,000,000	9,000,000
Pay-fixed Swaps, Fair Value, Gross Liability	6,000,000	5,000,000
Pay-fixed Swaps, Notional Amount	13,900,000,000	12,600,000,000
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Pay-fixed Swaps, Fair Value, Gross Liability		1,000,000
Pay-fixed Swaps, Notional Amount		495,000,000
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	138,000,000	142,000,000
Derivative Liability, Fair Value, Gross Liability	161,000,000	141,000,000
Derivative, Notional Amount	60,847,000,000	77,543,000,000
Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	5,000,000	13,000,000
Derivative Liability, Fair Value, Gross Liability	78,000,000	2,000,000
Derivative, Notional Amount	1,514,000,000	1,743,000,000
Equity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,000,000	0
Derivative Liability, Fair Value, Gross Liability	6,000,000	5,000,000
Derivative, Notional Amount	75,000,000	3,000,000
Interest Rate Swap [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	40,000,000	36,000,000
Derivative Liability, Fair Value, Gross Liability	65,000,000	44,000,000
Derivative, Notional Amount	11,979,000,000	13,613,000,000
Futures and Forwards [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	4,000,000	11,000,000
Derivative Liability, Fair Value, Gross Liability	2,000,000	3,000,000
Derivative, Notional Amount	18,886,000,000	29,836,000,000
Written Options [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	94,000,000	94,000,000
Derivative, Notional Amount	14,823,000,000	11,132,000,000
Written Options [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative, Notional Amount	0	17,000,000
Written Options [Member] \| Equity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	3,000,000	5,000,000
Derivative, Notional Amount	1,000,000	3,000,000
Purchased Options [Member] \| Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	94,000,000	95,000,000
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative, Notional Amount	15,159,000,000	22,962,000,000
Purchased Options [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative, Notional Amount	0	17,000,000
Purchased Options [Member] \| Equity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,000,000	0
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative, Notional Amount	0	0
Forward Contracts [Member] \| Equity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	3,000,000	0
Derivative, Notional Amount	74,000,000	0
Swap [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	12,000,000
Derivative Liability, Fair Value, Gross Liability	74,000,000	1,000,000
Derivative, Notional Amount	1,210,000,000	1,379,000,000
Foreign Exchange Forward [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	5,000,000	1,000,000
Derivative Liability, Fair Value, Gross Liability	4,000,000	1,000,000
Derivative, Notional Amount	304,000,000	330,000,000
Other Trading [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	145,000,000	155,000,000
Derivative Liability, Fair Value, Gross Liability	245,000,000	148,000,000
Derivative, Notional Amount	$ 62,436,000,000	$ 79,289,000,000

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- Definition

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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