Financial and Derivative Instruments (Details 2) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Offsetting Assets [Abstract]
Derivative Assets, Gross Amount Recognized	$ 999	$ 1,052
Derivative Assets, Gross Amounts Offset	926	1,020
Derivative Assets, Net Amounts Presented	73	32
Derivative Assets, Gross Amounts Not Offset	0	0
Derivative Assets, Net Amounts Presented	73	32
Offsetting Liabilities [Abstract]
Derivative Liabilities, Gross Amount Recognized	934	1,129
Derivative Liabilities, Gross Amounts Offset	926	1,020
Derivative Liabilities, Net Amounts Presented	8	109
Derivative Liabilities, Gross Amounts Not Offset	0	0
Derivative Liabilities, Net Amounts Presented	$ 8	$ 109