Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill And Intangible Assets [Line Items]
Amortization expense related to the intangible assets	$ 5,000,000	$ 5,000,000	$ 7,000,000
Expected amortization for the year 2025	5,000,000
Expected amortization for the year 2026	5,000,000
Expected amortization for the year 2027	5,000,000
Expected amortization for the year 2028	5,000,000
Expected amortization for the year 2029	5,000,000
Alumina [Member]
Goodwill And Intangible Assets [Line Items]
Goodwill impairment	$ 0

Goodwill and intangible assets.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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