Restructuring - Schedule of Restructuring Reserve (Details) - 2017 Plan $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	$ 186
Expensed	448
Cash payments	(425)
Foreign currency translation and other	(8)
Restructuring reserve, ending balance	$ 201

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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