Restructuring Actions - Roll Forward (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Employee-Related \| 2020 Restructuring Actions \| Other Restructuring
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance	$ 24
Cash Payments	(4)
Restructuring Reserve, Accrual Adjustment	(9)
Restructuring actions balances, Ending Balance	11
Operational/Marketing Capability Restructuring \| Employee-Related \| 2021 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance	101
Incremental expense incurred	14
Cash Payments	(14)
Restructuring actions balances, Ending Balance	101
Drug delivery business \| 2020 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance	24
Cash Payments	(1)
Restructuring Reserve, Accrual Adjustment	(1)
Restructuring actions balances, Ending Balance	22
Drug delivery business \| Employee-Related \| 2020 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance	15
Cash Payments	(1)
Restructuring Reserve, Accrual Adjustment	(1)
Restructuring actions balances, Ending Balance	13
Drug delivery business \| Asset-Related and Other \| 2020 Restructuring Actions
Restructuring Reserve Roll Forward
Restructuring actions balances, Beginning Balance	9
Restructuring actions balances, Ending Balance	$ 9

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.

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

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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.

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