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Acquisitions and Divestitures - 2018 Divestitures (Details) $ in Millions |  | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 USD ($) employee | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Business Acquisition [Line Items] |  |  |  |
Gain (loss) on disposition of business |  | $ (8) | $ (63) | $ (43)
Eger |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Consideration | $ 2 |  |  | 2
Gain (loss) on disposition of business |  |  |  | (43)
Number of employees | employee | 180 |  |  |
Engineered Structures | Eger |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Sales |  |  |  | $ 32

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