Restructuring Costs (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Restructuring and Related Cost [Abstract]
Restructuring costs	$ 37	$ 48
Employee Separation Charges [Roll Forward]
Liability balance at beginning of period	48	85	$ 85
Increase in liability (separation charges)	11		48
Reduction in liability (payments)	(16)		(85)
Liability balance at end of period	43		$ 48
Employee separations \| Other Operating Income (Expense)
Restructuring and Related Cost [Abstract]
Restructuring costs	11	15
Contract terminations \| Other Operating Income (Expense)
Restructuring and Related Cost [Abstract]
Restructuring costs	1	0
Long-lived asset impairments \| Other Operating Income (Expense)
Restructuring and Related Cost [Abstract]
Restructuring costs	9	7
Other \| Cost of Sales
Restructuring and Related Cost [Abstract]
Restructuring costs	$ 16	$ 26

As of the balance sheet date, the liability for employee separation charges.

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- Definition

Benefit payments made during the period in connection with employee separation programs.

+ References

No definition available.

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- References

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ References

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