Financial Instruments and Risk Management - General (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) shares approach $ / shares
Commodity contracts
Financial Instruments and Risk Management
Number of methods through which entity manages commodity price risk in connection with market price fluctuations of aluminum ingot | approach	2
Notional amount of contracts	$ 1,256
Net gain (loss) included in AOCI, after-tax	15
Net gain (loss) included in AOCI, after-tax, expected to be recognized in net earnings within the next 12 months	$ 14
Commodity contracts | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted hedge transactions in years	1 year
Currency
Financial Instruments and Risk Management
Notional amount of contracts	$ 2,404
Net gain (loss) included in AOCI, after-tax	(5)
Net gain (loss) included in AOCI, after-tax, expected to be recognized in net earnings within the next 12 months	$ 9
Currency | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted hedge transactions in years	2 years
Interest Rate
Financial Instruments and Risk Management
Notional amount of contracts	$ 600
Net gain (loss) included in AOCI, after-tax	7
Net gain (loss) included in AOCI, after-tax, expected to be recognized in net earnings within the next 12 months	$ 3
Interest Rate | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted hedge transactions in years	3 years
Net Investment
Financial Instruments and Risk Management
Notional amount of contracts	$ 1,050
Net gain (loss) included in AOCI, after-tax	$ 17
Net Investment | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted hedge transactions in years	5 years
Equity contracts
Financial Instruments and Risk Management
Combined notional value, shares | shares	1.4
Change in company's stock price (in dollars per share) | $ / shares	$ 1