| **Restructuring and Other Exit Costs - Additional Information (Details) - USD ($) $ in Millions** |         | 3 Months Ended |        |
|---------------------------------------------------------------------------------------------------|---------|----------------|--------|
||
| **Restructuring Cost and Reserve [Line Items]**                                                   |    |           |   |
| Restructuring liabilities                                                                         |    | $ 48           | $ 65   |
| Restructuring charges                                                                             |    | 3              |   |
| Employee severance-related costs                                                                  |    |           |   |
| **Restructuring Cost and Reserve [Line Items]**                                                   |    |           |   |
| Restructuring liabilities                                                                         |    | 41             | 58     |
| Restructuring charges                                                                             |    | 3              |   |
| Employee severance-related costs | L3Harris                                                       |    |           |   |
| **Restructuring Cost and Reserve [Line Items]**                                                   |    |           |   |
| Restructuring liabilities                                                                         |    | 38             |   |
| Facilities consolidation and other exit costs                                                     |    |           |   |
| **Restructuring Cost and Reserve [Line Items]**                                                   |    |           |   |
| Restructuring liabilities                                                                         |    | 7              | $ 7    |
| Remaining lease term (less than)                                                                  | 3 years |           |   |
| Restructuring charges                                                                             |    | 0              |   |
| Aviation Systems | Employee Severance, COVID-19 Related                                           |    |           |   |
| **Restructuring Cost and Reserve [Line Items]**                                                   |    |           |   |
| Restructuring liabilities                                                                         |    | $ 3            |   |

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Lessee, Operating Lease, Remaining Lease Term
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| - Definition
Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.
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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.
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