Asset Retirement Obligations - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2022	Jun. 30, 2022
Asset Retirement Obligations [Line Items]
Liabilities incurred	$ 9	$ 47
Capitalized asset retirement cost	1	8
Cost of Goods Sold [Member]
Asset Retirement Obligations [Line Items]
Additional asset retirement obligation liabilities incurred	8	$ 39
Magnesium Smelter Facility in Addy [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred	$ 15

Asset Retirement obligations.

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

+ Details

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- Definition

The amount of asset retirement costs previously incurred and capitalized separately from the capitalized amount of the associated long-lived assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=126939881&loc=d3e61901-109447

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- Definition

Amount of asset retirement obligations (ARO) costs incurred (whether capitalized or charged to expense) during the period.

+ References

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