Derivative Financial Instruments and Risk Management (Details 5) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Offsetting Assets and Liabilities
Gross Amount of Recognized Assets	$ 112	$ 22
Gross Amounts Offset	0	0
Net Amount of Assets	112	22
Gross Amounts Not Offset	(34)	(10)
Net Amount	78	12
Gross Amount of Recognized Liabilities	(63)	(68)
Gross Amounts Offset	0	0
Net Amount of Liabilities	(63)	(68)
Gross Amounts Not Offset	34	10
Net Amount	$ (29)	$ (58)