Restructuring - Schedule of Restructuring Reserve (Details) - 2017 Plan $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Restructuring Plan
Balance as of December 31, 2017	$ 186
Expensed	260
Cash payments	(248)
Foreign currency translation and other	(2)
Balance as of June 30, 2018	$ 196

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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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.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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