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Segment and Geographic Area Information - Additional Information (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) segment | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Mar. 31, 2020 USD ($) | Mar. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |  |
Number of reportable segments | segment | 4 |  |  |  |
Goodwill (A and P) | $ 4,102 | $ 4,067 | $ 4,186 |  |
Percentage of fair value in excess of carrying amount | 50.00% |  |  |  |
Engine Products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Goodwill (A and P) | $ 2,171 | $ 2,164 | $ 2,066 | $ 17 |
Engineered Structures |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Percentage of fair value in excess of carrying amount |  |  |  | 15.00% | 60.00%
Revenue Benchmark | Customer Concentration Risk | Aerospace |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Concentration risk, percentage | 69.00% | 71.00% | 70.00% |  |
Revenue Benchmark | Customer Concentration Risk | Aerospace | General Electric Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Concentration risk, percentage | 11.00% |  |  |  |

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