Derivative Instruments and Hedging Activities - Part 2 (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Liabilities
Derivative Liabilities, Gross		$ 363	$ 424
Derivative, Net Liability Position, Aggregate Fair Value	[1]	20	41
Collateral Already Posted, Aggregate Fair Value	[1]	10	18
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		341	376
Other Current Assets [Member]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		94	99
Other Current Liabilities [Member]
Liabilities
Derivative Liabilities, Gross		223	155
Other Noncurrent Assets [Member]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		247	277
Other Noncurrent Liabilities [Member]
Liabilities
Derivative Liabilities, Gross		140	269
Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		176	358
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		28	51
Not Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		187	66
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		313	325
Interest Rate Contract [Member]
Liabilities
Derivative Liabilities, Gross		301	300
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		13	18
Interest Rate Contract [Member] | Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		157	295
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		13	18
Interest Rate Contract [Member] | Not Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		144	5
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		0	0
Cross currency derivatives [Member]
Liabilities
Derivative Liabilities, Gross		14	18
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		5	4
Cross currency derivatives [Member] | Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		14	18
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		5	4
Cross currency derivatives [Member] | Not Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		0	0
Foreign Exchange Contract [Member]
Liabilities
Derivative Liabilities, Gross		29	64
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		270	309
Foreign Exchange Contract [Member] | Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		0	19
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		0	9
Foreign Exchange Contract [Member] | Not Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		29	45
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		270	300
Commodity Contract [Member]
Liabilities
Derivative Liabilities, Gross		19	42
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		53	45
Commodity Contract [Member] | Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		5	26
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		10	20
Commodity Contract [Member] | Not Designated as Hedging Instruments [Member]
Liabilities
Derivative Liabilities, Gross		14	16
Derivative Asset, Fair Value, Amount Not Offset Against Collateral [Abstract]
Derivative Assets, Gross		$ 43	$ 25

[1] (1) Based on the credit rating of certain subsidiaries