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Goodwill and Intangible Assets - Changes In Carrying Amount of Goodwill by Reporting Unit (Details) $ in Millions | 6 Months Ended
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Jul. 04, 2021 USD ($)
Goodwill [Roll Forward] |  |
Goodwill, beginning of period | $ 20,053 | [1]
Acquisitions | 27 | [2]
Other | (59) | [3]
Goodwill, end of period | 20,021 | [1]
Aerospace |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning of period | 3,065 | [1]
Acquisitions | 27 | [2]
Other | (72) | [3]
Goodwill, end of period | 3,020 | [1]
Marine Systems |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning of period | 297 | [1]
Acquisitions | 0 | [2]
Other | 0 | [3]
Goodwill, end of period | 297 | [1]
Combat Systems |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning of period | 2,786 | [1]
Acquisitions | 0 | [2]
Other | 6 | [3]
Goodwill, end of period | 2,792 | [1]
Technologies |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning of period | 13,905 | [1]
Acquisitions | 0 | [2]
Other | 7 | [3]
Goodwill, end of period | 13,912 | [1]
Accumulated impairment losses | $ 1,800 |
[1] | Goodwill in the Technologies reporting unit was net of $1.8 billion of accumulated impairment losses.
[2] | Included adjustments during the purchase price allocation period.
[3] | Consisted primarily of adjustments for foreign currency translation.

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