Other Liabilities - Workforce Reduction and Environmental Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Other Liabilities
Total amounts accrued for workforce reductions	$ 3,151	$ 950
Charge for structural actions	2,036
Total amounts accrued for non-ARO environmental liabilities	266	270
Total amounts accrued for ARO liabilities	$ 154	$ 150

It represents the amount of workforce reduction actions to improve productivity, cost competitiveness and to rebalance skills.

No definition available.

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- Definition

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

+ References

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-Name Accounting Standards Codification
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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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- References

No definition available.

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- Definition

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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