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Acquisitions and Divestitures - 2020 Divestitures (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Jan. 31, 2020
Business Acquisition [Line Items] |  |  |  |
Asset impairment charges | $ 5 | $ 442 | $ 9 |
Small Manufacturing Facility In The United Kingdom | Engineered Structures |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Consideration |  |  |  | $ 12
Asset impairment charges | $ 5 |  |  |

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