Derivative Financial Instruments Derivative Financial Instruments (Schedule of Gains/(losses) reclassified from AOCI to Earnings) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating Expense
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ (2)		$ (3)	$ 1
General and Administrative Expense
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(1)	(1)	(1)
Sales
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax		1	(1)	6
Operating Expense
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(5)	(7)	(6)	(12)
General and Administrative Expense
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ (5)	$ 8	$ (5)	$ 9