Financial Instruments and Risk Management - General (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) approach $ / shares shares	Dec. 31, 2021 USD ($)
Financial Instruments and Risk Management
Collateral amount posted for derivative instruments with credit-risk-related contingent features that were in a net liability position	$ 0	$ 0
Commodity
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	$ 1,610
Net gain (loss) included in AOCI, after-tax	(23)
Net gain (loss) included in AOCI, after-tax, expected to be recognized in net earnings within the next 12 months	$ (23)
Commodity | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted cash flow hedge transactions in years	2 years
Currency
Financial Instruments and Risk Management
Notional amount of contracts	$ 3,216
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	$ 19
Currency | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted cash flow hedge transactions in years	2 years
Interest Rate
Financial Instruments and Risk Management
Notional amount of contracts	$ 214
Interest Rate | Cash Flow Hedging
Financial Instruments and Risk Management
Longest duration of forecasted cash flow hedge transactions in years	1 year
Equity contracts
Financial Instruments and Risk Management
Combined notional value (in shares) | shares	2.5
Change in company's stock price (in dollars per share) | $ / shares	$ 1