Restructuring and Other Charges - Summary (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring and Related Activities [Abstract]
Layoff costs	$ 17	$ 0	$ 93	$ 68
Reversals of previously recorded layoff reserves	0	0	(10)	(2)
Settlements	3	4	67	(8)
Non-cash asset impairments	0	8	0	442
Net loss on divestitures of assets and businesses	0	42	9	54
Other	2	2	7	18
Restructuring and other charges	$ 22	$ 56	$ 166	$ 572

Gain (Loss) On Divestitures Of Assets And Business, Included In Restructuring Charges

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Reversal Of Previous Severance Costs

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses 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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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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