Derivative Instruments and Hedging Activities (Assets and LIabilities - Designated vs. Not Designated Hedging Instruments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Total asset derivatives	$ 240	$ 100
Total liability derivatives	371	602
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	113	8
Total liability derivatives	351	565
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	127	92
Total liability derivatives	20	37
Interest Rate Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	98	2
Total liability derivatives	322	565
Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	96	0
Total liability derivatives	318	544
Interest Rate Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	2	2
Total liability derivatives	4	21
Cross Currency Interest Rate Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	5	6
Total liability derivatives	11	6
Cross Currency Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	5	6
Total liability derivatives	11	6
Cross Currency Interest Rate Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	0	0
Total liability derivatives	0	0
Foreign Exchange Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	113	81
Total liability derivatives	21	14
Foreign Exchange Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	4	0
Total liability derivatives	15	7
Foreign Exchange Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	109	81
Total liability derivatives	6	7
Other Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	24	11
Total liability derivatives	17	17
Other Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	8	2
Total liability derivatives	7	8
Other Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	16	9
Total liability derivatives	$ 10	$ 9