| **Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)** | 3 Months Ended |
|---------------------------------------------------------------------------------------|----------------|
||
| **Finite-Lived Intangible Assets [Line Items]**                                       |           |   |   |
| Impairment of goodwill                                                                | $ 301,000,000  | $ 0 |   |
| L3Harris                                                                              |           |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                       |           |   |   |
| Amortization expense for intangible assets                                            | 158,000,000    |   |   |
| Exelis                                                                                |           |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                       |           |   |   |
| Amortization expense for intangible assets                                            |           |   | $ 29,000,000 |
| Commercial Aviation Solutions                                                         |           |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                       |           |   |   |
| Impairment of goodwill                                                                | 296,000,000    |   |   |
| Goodwill impairment loss attributable to noncontrolling interests                     | $ 28,000,000   |   |   |

| X                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Goodwill, Impairment Loss, Attributable To Noncontrolling Interests
+ References
No definition available.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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No definition available.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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