Commitments and Contingencies Environmental (Details) - Environmental Issue $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) site	Mar. 31, 2021 USD ($)
Loss Contingencies [Line Items]
Number of alleged environmental contamination sites \| site	185
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning balance	$ 251	$ 265
Accruals / changes in estimates	1	1
Payments	(4)	(5)
Ending balance	248	261
Current portion of ending balance	35	$ 35
Minimum
Loss Contingencies [Line Items]
Possible future costs to settle claims and associated liability	200
Maximum
Loss Contingencies [Line Items]
Possible future costs to settle claims and associated liability	$ 335

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

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Administrative, Judicial and Other Mandatory Cleanup Efforts, Total Sites

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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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