v3.20.2

Restructuring and Other Charges - Narrative (Details) $ in Millions |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 01, 2020 USD ($) | Jun. 30, 2020 USD ($) employee claimants | Jun. 30, 2019 USD ($) employee | Jun. 30, 2020 USD ($) employee | Jun. 30, 2019 USD ($) employee | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | $ 77 | $ 38 | $ 58 | $ 40 |  |
Restructuring and other charges |  | $ 77 | 38 | 58 | 40 |  |
Number of employees separated | employee |  | 410 |  |  |  |  |
Cash payments, restructuring |  |  |  | $ 13 |  |  | $ 15
Forecast |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Cash payments, restructuring |  |  |  |  |  | $ 7 |
2020 Restructuring Program [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Expected number of employees separated | employee |  |  |  | 550 |  |  |
Number of employees separated | employee |  |  |  | 150 |  |  |
2019 Restructuring Program [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Expected number of employees separated | employee |  |  |  | 380 |  |  |
Number of employees separated | employee |  |  |  | 320 |  |  |
2019 Restructuring Program [Member] | Previously Reported [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Expected number of employees separated | employee |  |  |  | 480 |  |  |
Layoff costs |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | $ 17 |  |  |  |  |
Cash payments, restructuring |  |  |  | $ 11 |  |  | 12
Layoff costs | 2020 Restructuring Program [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Cash payments, restructuring |  | 5 |  |  |  |  |
Layoff costs | 2019 Restructuring Program [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Cash payments, restructuring |  | 2 |  | 6 |  |  |
Allocated costs, ParentCo |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 0 | $ 12 | 2 | 3 |  |
Other miscellaneous costs |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 2 |  | 4 | 2 |  |
Cash payments, restructuring |  |  |  | $ 2 |  |  | $ 3
Pension Settlement Cost [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 55 |  |  |  |  |
Reversal of Reserve [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 12 |  |  |  |  |
Environmental [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 5 |  |  |  |  |
Legacy Non-Income Taxes [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | 4 |  |  |  |  |
Impairment of Carrying Value of Tradename [Member] |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | $ 10 |  |
Hard Alloy Extrusions Plant in South Korea | Disposed of by sale |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Gain (loss) on sale | $ 31 | 1 |  |  |  |  |
Rolled Products and Building and Construction Systems |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Number of employees separated | employee |  |  | 95 |  | 250 |  |
Rolled Products and Building and Construction Systems | Layoff costs |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  |  | $ 14 |  | $ 25 |  |
Building and Construction System and Extrustions [Member] | Layoff costs |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | $ 8 |  |  |  |  |
Number of employees separated | claimants |  | 140 |  |  |  |  |
Building and Construction System and Extrustions [Member] | Other miscellaneous costs |  |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  | $ 11 |  |  |  |  |

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