v3.20.2

Restructuring and Other Charges - Restructuring Reserve (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2020 USD ($) employee claimants | Jun. 30, 2019 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2019 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  | $ 21 | $ 4 | $ 21 | $ 4
Cash payments |  |  | (13) |  |  | (15)
Restructuring charges |  |  | 27 |  |  | 32
Other |  |  | (7) |  |  | 0
Ending balance | $ 30 |  | 30 |  |  | 21
Restructuring and other charges | (77) | $ (38) | (58) | (40) |  |
Separation-related adjustments (A) | 314 |  | 314 |  |  |
Restructuring and other charges | $ 77 | 38 | 58 | 40 |  |
Number of employees separated | employee | 410 |  |  |  |  |
Forecast |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Cash payments |  |  |  |  | (7) |
Hard Alloy Extrusions Plant in South Korea |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Gain (Loss) on Disposition of Business |  |  | 25 |  |  |
Aluminum Rolling Mill in Brazil |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Gain (Loss) on Disposition of Business |  |  | 25 |  |  |
Operating segments |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | $ (15) | (26) | (6) | (37) |  |
Rolled Products [Member] |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | (7) | (2) | (16) | (8) |  |
Building and Construction Systems [Member] |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | (5) | (24) | (6) | (29) |  |
Extrusions [Member] |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | (3) | 0 | (28) | 0 |  |
Corporate Segment |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | (62) | (12) | (64) | (3) |  |
Layoff costs |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  | 20 | 1 | 20 | 1
Cash payments |  |  | (11) |  |  | (12)
Restructuring charges |  |  | 25 |  |  | 30
Other |  |  | (7) |  |  | 1
Ending balance | 29 |  | 29 |  |  | 20
Restructuring and other charges | (17) |  |  |  |  |
Separation-related adjustments (A) |  |  | 2 |  |  |
Layoff costs | Building and Construction System and Extrustions [Member] |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | $ (8) |  |  |  |  |
Number of employees separated | claimants | 140 |  |  |  |  |
Other costs |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  | 1 | 3 | $ 1 | 3
Cash payments |  |  | (2) |  |  | (3)
Restructuring charges |  |  | 2 |  |  | 2
Other |  |  | 0 |  |  | (1)
Ending balance | $ 1 |  | 1 |  |  | $ 1
Restructuring and other charges | (2) |  | (4) | (2) |  |
Separation-related adjustments (A) |  |  | 0 |  |  |
Other costs | Building and Construction System and Extrustions [Member] |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | (11) |  |  |  |  |
Spin-off |  |  |  |  |  |
Restructuring Reserve [Roll Forward] |  |  |  |  |  |
Restructuring and other charges | $ 0 | $ (12) | (2) | $ (3) |  |
Separation-related adjustments (A) |  |  | $ 2 |  |  |

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