v3.22.4

Summary of Significant Accounting Policies - Narrative (Details) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2022 USD ($) report | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Sep. 30, 2022 USD ($)
Goodwill [Line Items] |  |  |  |  |
Number of reporting units | report |  | 3 |  |  |
Carrying value of goodwill | $ 322,000,000 | $ 292,000,000 | $ 322,000,000 | $ 390,000,000 |
Maximum period between quantitative goodwill impairment tests |  | 3 years |  |  |
Goodwill impairment |  | $ 0 | 65,000,000 | 0 |
Accumulated impairment losses | $ 93,000,000 | 93,000,000 | 93,000,000 | 28,000,000 |
Goodwill and Intangible Asset Impairment |  | 0 | 65,000,000 | 0 |
Weighted Average Cost of Capital, Basis Points | 15000.00% |  |  |  |
Rolled Products |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Carrying value of goodwill | $ 253,000,000 | 224,000,000 | 253,000,000 | 254,000,000 | $ 232,000,000
Goodwill impairment |  | 0 | 0 |  |
Accumulated impairment losses | 0 | 0 | 0 | 0 |
Building and Construction Systems |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Carrying value of goodwill | 69,000,000 | 68,000,000 | 69,000,000 | 71,000,000 | $ 67,000,000
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 | 0 | 65,000,000 |
Goodwill impairment |  |  | 65,000,000 |  |
Accumulated impairment losses | $ 65,000,000 | 65,000,000 | $ 65,000,000 | $ 0 |
Financing Receivable |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Financing Receivable, Capacity |  | $ 250,000,000 |  |  |

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