v3.22.4

Financial Instruments (Details) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2022 USD ($) kiloMetricTon MMBTU	Mar. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 USD ($) kiloMetricTon MMBTU	Dec. 31, 2021 USD ($) kiloMetricTon MMBTU	Dec. 31, 2020 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 5			$ 5	$ 1
Derivative Liability	8			8	23
Unrealized Gain (Loss) on Cash Flow Hedging Instruments				95	(161)	$ (2)
Realized Gain (Loss) on Cash Flow Hedging Instruments				67	(140)	(8)
Unrealized Gain (Loss) on Derivatives				6	0	0
Aluminum Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset	6			6	1
Derivative Liability	$ 12			$ 12	$ 3
Aluminum Contract | Not Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	60			60	14
Aluminum Contract | Not Designated as Hedging Instrument | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	53			53	19
Aluminum Contract | Not Designated as Hedging Instrument | Sales
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Derivatives	$ 4
Realized Gain (Loss) on Derivatives				$ 6
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset	0			0	$ 0
Derivative Liability	$ (14)			$ (14)	$ 18
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	17			17	0
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	368			368	251
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument | Sales
Derivatives, Fair Value [Line Items]
Realized Gain (Loss) on Cash Flow Hedging Instruments				$ 43	$ (150)	2
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument | Cost of Sales
Derivatives, Fair Value [Line Items]
Realized Gain (Loss) on Cash Flow Hedging Instruments				(5)	(8)	10
Aluminum Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments				81	(160)	(7)
Energy Related Derivative | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability	$ 4			$ 4	$ 0
Energy Related Derivative | Not Designated as Hedging Instrument | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	0.6			0.6	0
Energy Related Derivative | Not Designated as Hedging Instrument | Cost of Sales
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Derivatives		$ 5	$ 2	$ 4	$ 6
Realized Gain (Loss) on Derivatives				3
Energy Related Derivative | Cash Flow Hedging | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability	$ 5			$ 5	$ 2
Energy Related Derivative | Cash Flow Hedging | Designated as Hedging Instrument | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	6.3			6.3	3.3
Energy Related Derivative | Cash Flow Hedging | Designated as Hedging Instrument | Cost of Sales
Derivatives, Fair Value [Line Items]
Realized Gain (Loss) on Cash Flow Hedging Instruments				$ (20)	$ 0	0
Energy Related Derivative | Cash Flow Hedging | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments				16	(2)	0
Commodity Contract | Cash Flow Hedging | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset	$ (1)			(1)	0
Derivative Liability	$ 1			$ 1	$ 0
Commodity Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	1			1	0
Commodity Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | kiloMetricTon	3			3	0
Commodity Contract | Cash Flow Hedging | Designated as Hedging Instrument | Cost of Sales
Derivatives, Fair Value [Line Items]
Realized Gain (Loss) on Cash Flow Hedging Instruments				$ 1	$ (2)	0
Commodity Contract | Cash Flow Hedging | Designated as Hedging Instrument | Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments				(2)	1	$ 5
Natural Gas Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 16			$ 16
Natural Gas Contract | Not Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	12.1			12.1
Natural Gas Contract | Not Designated as Hedging Instrument | Cost of Sales
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Derivatives				$ 16
Estimate of Fair Value Measurement
Derivatives, Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	$ 261			261	335
Derivative Asset	21			21	1
Derivative Liability	8			8	23
Fair value of long-term debt	1,539			1,539	1,692
Reported Value Measurement
Derivatives, Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	261			261	335
Derivative Asset	21			21	1
Derivative Liability	8			8	23
Fair value of long-term debt	$ 1,597			$ 1,597	$ 1,594

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