Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	$ 58	$ 59	$ 93
Cash payments	(49)	(65)	(86)
Restructuring charges	124	65	97
Other	108	1	45
Restructuring reserve ending balance	25	58	59
Restructuring and other charges	(9)	(165)	(155)
Layoff costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	56	50	84
Cash payments	(47)	(59)	(73)
Restructuring charges	111	64	70
Other	110	(1)	31
Restructuring reserve ending balance	10	56	50
Reversal of prior restructuring charges
Restructuring Reserve [Roll Forward]
Other	25
Restructuring and other charges	19	11
Reclassification of a stock awards reversal
Restructuring Reserve [Roll Forward]
Restructuring and other charges		(13)
Reclassification of pension costs
Restructuring Reserve [Roll Forward]
Other	2
Restructuring and other charges	(119)
Effects of foreign currency translation and other
Restructuring Reserve [Roll Forward]
Other	4		(1)
Credit in post-retirement costs
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(28)
Other exit costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	2	9	9
Cash payments	(2)	(6)	(13)
Restructuring charges	13	1	27
Other	(2)	2	14
Restructuring reserve ending balance	15	2	9
Restructuring and other charges	(19)	$ (69)	(57)
Reclassification of asset retirement obligation
Restructuring Reserve [Roll Forward]
Restructuring and other charges			8
Reclassification of environmental obligation
Restructuring Reserve [Roll Forward]
Restructuring and other charges			2
Reclassification of legal obligations
Restructuring Reserve [Roll Forward]
Restructuring and other charges			$ 4
Minimum \| Contract Termination
Restructuring Reserve [Roll Forward]
Restructuring reserve ending balance	5
Maximum \| Contract Termination
Restructuring Reserve [Roll Forward]
Restructuring reserve ending balance	$ 7

Restructuring reserve period expenses.

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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- Definition

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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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

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

+ References

No definition available.

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