Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	$ 54
Cash payments	(24)
Restructuring and other charges	9	$ 39
Other	(10)
Restructuring reserve ending balance	29
Settlements	3	0
Accelerated depreciation	1
Pension benefits
Restructuring Reserve [Roll Forward]
Settlements	3	0
Layoff costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	54
Cash payments	(24)
Restructuring and other charges	4	$ 22
Other	(5)
Restructuring reserve ending balance	29
Other exit costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	0
Cash payments	0
Restructuring and other charges	5
Other	(5)
Restructuring reserve ending balance	0
Accelerated depreciation	1
Other Layoffs Costs
Restructuring Reserve [Roll Forward]
Restructuring and other charges	2
Facility closing \| Small Manufacturing Business
Restructuring Reserve [Roll Forward]
Restructuring and other charges	$ 4

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 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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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.

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Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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