Asset Retirement Obligations - Changes in Carrying Values of Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Asset Retirement Obligations [Roll Forward]
Balance at beginning of year	$ 60	$ 58
Additional obligations incurred	3	5
Obligations settled	(7)	(7)
Change in estimate of obligations	(1)	0
Foreign currency translation effects	(1)	1
Accretion expense	12	3
Balance at end of period	$ 66	$ 60

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.

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-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations.

+ References

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Amount of asset retirement obligations incurred during the period.

+ References

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-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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-Section 50
-Paragraph 1
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Asset Retirement Obligation, Accretion Expense Accrued

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No definition available.

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