v3.22.0.1

Summary of Significant Accounting Policies - Narrative (Details) | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) reporting_unit | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Sep. 30, 2021 USD ($) | Jan. 01, 2019 USD ($)
Goodwill [Line Items] |  |  |  |  |  |
Number of reporting units | reporting_unit |  | 3 |  |  |  |
Carrying value of goodwill | $ 322,000,000 | $ 322,000,000 | $ 390,000,000 | $ 386,000,000 |  |
Maximum period between quantitative goodwill impairment tests |  | 3 years |  |  |  |
Goodwill impairment |  | $ 65,000,000 | 0 | 0 |  |
Accumulated impairment losses | $ 93,000,000 | 93,000,000 | 28,000,000 | 28,000,000 |  |
Goodwill and Intangible Asset Impairment |  | 65,000,000 | 0 | 0 |  |
Weighted Average Cost of Capital, Basis Points | 15000.00% |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Operating lease right-of-use assets | $ 122,000,000 | 122,000,000 | 144,000,000 |  |  | $ 150,000,000
Operating lease liabilities | 125,000,000 | 125,000,000 |  |  |  | $ 150,000,000
Reclassification from other noncurrent liabilities and deferred credits | (85,000,000) | (85,000,000) | (102,000,000) |  |  |
Reclassification from properties, plants, and equipment, net | (2,651,000,000) | (2,651,000,000) | (2,712,000,000) |  |  |
Reclassification from deferred income tax assets | (229,000,000) | (229,000,000) | (329,000,000) |  |  |
Rolled Products |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Carrying value of goodwill | 253,000,000 | 253,000,000 | 254,000,000 | 246,000,000 | $ 254,000,000 |
Goodwill impairment |  | 0 |  |  |  |
Accumulated impairment losses | 0 | 0 | 0 | 0 |  |
Building and Construction Systems |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Carrying value of goodwill | 69,000,000 | 69,000,000 | 71,000,000 | 69,000,000 | 70,000,000 |
Goodwill impairment |  | 0 |  |  |  |
Accumulated impairment losses | 28,000,000 | 28,000,000 | 28,000,000 | 28,000,000 |  |
Extrusions |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Carrying value of goodwill | 0 | 0 | 65,000,000 | 71,000,000 | $ 65,000,000 |
Goodwill impairment |  | 65,000,000 |  |  |  |
Accumulated impairment losses | $ 65,000,000 | 65,000,000 | $ 0 | 0 |  |
Rolled Products and Building and Construction Systems |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Goodwill impairment |  | $ 0 |  |  |  |
Adoption of accounting standard |  |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |  |
Reclassification to Parent Company net investment |  |  |  | 73,000,000 |  |
Reclassification from other noncurrent liabilities and deferred credits |  |  |  | 119,000,000 |  |
Reclassification from properties, plants, and equipment, net |  |  |  | 24,000,000 |  |
Reclassification from deferred income tax assets |  |  |  | $ 22,000,000 |  |

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