Restructuring - Restructuring Costs (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Reductions of global workforce
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 29	$ 78

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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