Commitments and Contingencies Environmental (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) site	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Accrual for Environmental Loss Contingencies [Roll Forward]
Number of sites the Company participates in environmental studies, cleanup or both \| site	190
Environmental Issue
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning balance	$ 265	$ 282	$ 298
Accruals / changes in estimates	3	2	5
Payments	(17)	(19)	(21)
Ending balance	251	265	282
Current portion of ending balance	35	$ 35	$ 40
Environmental Issue \| Minimum
Accrual for Environmental Loss Contingencies [Roll Forward]
Future costs to settle claims and associated liability	205
Environmental Issue \| Maximum
Accrual for Environmental Loss Contingencies [Roll Forward]
Future costs to settle claims and associated liability	$ 340

Amount of expense for newly incurred environmental loss contingencies and revisions to previously reported estimates

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Number of Sites The Company Participates in Environmental Studies, Cleanup or Both

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of cash outflow to settle environmental loss contingencies.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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