Business Restructuring (Schedule of Restructuring Activity) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring Reserve	$ 91		$ 110
Payments for Restructuring	15	$ 17
Release of business restructuring reserves	(3)	$ 0
Restructuring Reserve, Translation Adjustment	$ (1)

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.

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

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