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Asset Retirement Obligations (Tables)

9 Months Ended

Sep. 30, 2021

Asset Retirement Obligation Disclosure [Abstract]

Asset retirement obligations

			Asset Retirement Obligations
(Dollars in millions)
Balance at December 31, 2020			$	377
Additional liabilities accrued			26
Revisions in estimated cash outflows			43
Disposition of assets			(1)
Accretion expense			17
Balance at September 30, 2021			$	462

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- References

No definition available.

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- Definition

Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859

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