Interim Statement Presentation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Interim Statement Presentation [Line Items]
Postemployment Benefits, Period Expense	$ 14	$ 2	$ 27	$ 15
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Current	67		67
Impairment of Long-Lived Assets to be Disposed of	68
Capitalized Computer Software, Impairments	48
One-time Termination Benefits
Interim Statement Presentation [Line Items]
Restructuring Charges	40	$ 12	45	$ 15
Restructuring Reserve, Current	$ 48		$ 48

[Line Items] for Interim Statement Presentation [Table]

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Amount of impairment loss from capitalized computer software costs.

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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Period expense related to postemployment benefits.

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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 as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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