Derivative Instruments and Hedging Activities (Assets and LIabilities - Designated vs. Not Designated Hedging Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Total asset derivatives	$ 376	$ 375
Total liability derivatives	424	490
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	51	38
Total liability derivatives	358	448
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	325	337
Total liability derivatives	66	42
Interest Rate Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	18	0
Total liability derivatives	300	358
Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	18	0
Total liability derivatives	295	358
Interest Rate Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	0	0
Total liability derivatives	5	0
Cross Currency Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	4	0
Total liability derivatives	18	43
Cross Currency Interest Rate Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	4	0
Total liability derivatives	18	43
Cross Currency Interest Rate Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	0	0
Total liability derivatives	0	0
Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	309	327
Total liability derivatives	64	56
Foreign Exchange Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	9	8
Total liability derivatives	19	35
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	300	319
Total liability derivatives	45	21
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	45	48
Total liability derivatives	42	33
Commodity Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	20	30
Total liability derivatives	26	12
Commodity Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	25	18
Total liability derivatives	$ 16	$ 21