v3.23.2

Fair Value Measures and Disclosures (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 USD ($) MMBTU kiloMetricTon MWh | Jun. 30, 2022 USD ($) | Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($) | Jun. 30, 2023 USD ($) MMBTU kiloMetricTon MWh | Jun. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) MMBTU kiloMetricTon
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Asset | $ 53 |  |  |  | $ 53 |  | $ 21
Derivative Liability | 14 |  |  |  | 14 |  | 8
Unrealized Gain (Loss) on Cash Flow Hedging Instruments | 55 | $ 201 |  |  | 34 | $ 58 |
Realized Gain (Loss) on Cash Flow Hedging Instruments | 11 | (46) |  |  | 5 | (99) |
Unrealized Gain (Loss) on Derivatives | 18 | 21 |  |  | (2) | 23 |
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Asset | 48 |  |  |  | 48 |  | 0
Derivative Liability | 0 |  |  |  | 0 |  | $ (14)
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging | Other Comprehensive Income (Loss) |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Cash Flow Hedging Instruments | $ 58 | 203 |  |  | $ 49 | 47 |
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging | Other Assets |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | 242 |  |  |  | 242 |  | 17
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | kiloMetricTon | 29 |  |  |  | 29 |  | 368
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging | Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Realized Gain (Loss) on Cash Flow Hedging Instruments | $ 18 | (53) |  |  | $ 17 | (107) |
Designated as Hedging Instrument | Aluminum Contract | Cash Flow Hedging | Cost of Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Realized Gain (Loss) on Cash Flow Hedging Instruments | 0 | 0 |  |  | 0 | (1) |
Designated as Hedging Instrument | Commodity Contract | Cash Flow Hedging |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Asset | (1) |  |  |  | (1) |  | $ (1)
Derivative Liability | 1 |  |  |  | 1 |  | $ 1
Designated as Hedging Instrument | Commodity Contract | Cash Flow Hedging | Other Comprehensive Income (Loss) |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Cash Flow Hedging Instruments | $ (2) | (2) |  |  | $ (1) | (2) |
Designated as Hedging Instrument | Commodity Contract | Cash Flow Hedging | Other Assets |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | kiloMetricTon | 1 |  |  |  | 1 |  | 1
Designated as Hedging Instrument | Commodity Contract | Cash Flow Hedging | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | kiloMetricTon | 6 |  |  |  | 6 |  | 3
Designated as Hedging Instrument | Commodity Contract | Cash Flow Hedging | Cost of Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Realized Gain (Loss) on Cash Flow Hedging Instruments | $ 1 | 0 |  |  | $ 1 | 0 |
Designated as Hedging Instrument | Energy Related Derivative | Cash Flow Hedging |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Liability | 9 |  |  |  | 9 |  | $ 5
Designated as Hedging Instrument | Energy Related Derivative | Cash Flow Hedging | Other Comprehensive Income (Loss) |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Cash Flow Hedging Instruments | $ (1) | 0 |  |  | $ (14) | 13 |
Designated as Hedging Instrument | Energy Related Derivative | Cash Flow Hedging | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | MMBTU | 7.5 |  |  |  | 7.5 |  | 6.3
Designated as Hedging Instrument | Energy Related Derivative | Cash Flow Hedging | Cost of Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Realized Gain (Loss) on Cash Flow Hedging Instruments | $ 6 | (7) |  |  | $ 11 | (7) |
Not Designated as Hedging Instrument |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Derivatives | 18 | 24 |  |  | (2) | 29 |
Realized Gain (Loss) on Derivatives | (14) | 4 |  |  | (11) | 2 |
Not Designated as Hedging Instrument | Aluminum Contract |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Asset | 9 |  |  |  | 9 |  | $ 6
Derivative Liability | $ 2 |  |  |  | $ 2 |  | $ 12
Not Designated as Hedging Instrument | Aluminum Contract | Other Assets |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | kiloMetricTon | 33 |  |  |  | 33 |  | 60
Not Designated as Hedging Instrument | Aluminum Contract | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | kiloMetricTon | 1 |  |  |  | 1 |  | 53
Not Designated as Hedging Instrument | Aluminum Contract | Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Derivatives | $ 19 | 4 |  |  | $ 14 | 6 |
Realized Gain (Loss) on Derivatives | (10) | 4 |  |  | (6) | 2 |
Not Designated as Hedging Instrument | Energy Related Derivative |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Asset | (3) |  |  |  | (3) |  | $ 16
Derivative Liability | $ 2 |  |  |  | $ 2 |  | $ 4
Not Designated as Hedging Instrument | Energy Related Derivative | Other Assets |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | MMBTU | 4.7 |  |  |  | 4.7 |  | 12.1
Not Designated as Hedging Instrument | Energy Related Derivative | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | MMBTU | 2.7 |  |  |  | 2.7 |  | 0.6
Not Designated as Hedging Instrument | Energy Related Derivative | Cost of Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Derivatives | $ 1 | (20) |  |  | $ 16 | (23) |
Realized Gain (Loss) on Derivatives | 4 | 0 |  |  | 5 | 0 |
Not Designated as Hedging Instrument | Natural Gas Contract | Cost of Sales |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Unrealized Gain (Loss) on Derivatives |  |  | $ 6 | $ 2 |  | $ (5) |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | $ 3 |  |  |  |  |
Not Designated as Hedging Instrument | Electricity Derivative |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative Liability | $ 0 |  |  |  | $ 0 |  | $ 0
Not Designated as Hedging Instrument | Electricity Derivative | Other Liabilities |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount | MWh | 8,314 |  |  |  | 8,314 |  |
Reported Value Measurement |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Cash and Cash Equivalents, Fair Value Disclosure | $ 266 |  |  |  | $ 266 |  | 261
Derivative Asset | 53 |  |  |  | 53 |  | 21
Derivative Liability | 14 |  |  |  | 14 |  | 8
Debt, fair value | 1,598 |  |  |  | 1,598 |  | 1,597
Estimate of Fair Value Measurement |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |
Cash and Cash Equivalents, Fair Value Disclosure | 266 |  |  |  | 266 |  | 261
Derivative Asset | 53 |  |  |  | 53 |  | 21
Derivative Liability | 14 |  |  |  | 14 |  | 8
Debt, fair value | $ 1,620 |  |  |  | $ 1,620 |  | $ 1,539

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