Derivative and Other Financial Instruments (Schedule of Offsetting Derivative Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative assets
Gross amounts recognized in the Balance Sheet	$ 83	$ 47
Gross amounts not offset in the Balance Sheet	16	19
Net amount	67	28
Derivative liabilities
Gross amounts recognized in the Balance Sheet	49	59
Gross amounts not offset in the Balance Sheet	16	19
Net amount	$ 33	$ 40

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