Date the restructuring activities were initiated or are expected to be initiated, in CCYY-MM-DD format.

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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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Restructuring Charges (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Feb. 29, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Charges		$ 34	$ 64
Restructuring Reserve		7	13	$ 4
Restructuring, 2013 [Member[
Restructuring Charges			2
Restructuring, 2015 [Member]
Restructuring Charges			$ 62
Restructuring, 2016 [Member]
Restructuring Charges		34
Restructuring and Related Activities, Initiation Date	Feb. 01, 2016
Restructuring 2016 [Member]
Restructuring Charges		$ 34