| **Goodwill (Details) - USD ($) $ in Millions**                                                              | 3 Months Ended | 6 Months Ended | 12 Months Ended |
|-------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|
||
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill, Beginning Balance                                                                                 |           |           | $ 6,348         | $ 6,348 | $ 1,711 |   |
| Goodwill acquired                                                                                           |           |           |            |   | 4,695 |   |
| Goodwill decrease from divestitures                                                                         |           |           | (61)            |   | (24) |   |
| Currency translation adjustments                                                                            |           |           |            | (62) | (34) |   |
| Impairment of goodwill                                                                                      |           |           |            | (290) |   |   |
| Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed) |           |           |            | 40 |   |   |
| Goodwill, Ending Balance                                                                                    | $ 5,975        |           |            | 5,975 | 6,348 | $ 1,711 |
| Impairment of goodwill and other assets                                                                     |           | $ (367)        |            | (367) | (46) | 0 |
| Communication Systems                                                                                       |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill, Beginning Balance                                                                                 |           |           | 760             | 760 | 439 |   |
| Goodwill acquired                                                                                           |           |           |            |   | 326 |   |
| Goodwill decrease from divestitures                                                                         |           |           |            | 0 | 0 |   |
| Currency translation adjustments                                                                            |           |           |            | 7 | (5) |   |
| Impairment of goodwill                                                                                      |           |           |            | 0 |   |   |
| Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed) |           |           |            | 14 |   |   |
| Goodwill, Ending Balance                                                                                    | 781            |           |            | 781 | 760 | 439 |
| Space and Intelligence Systems                                                                              |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill, Beginning Balance                                                                                 |           |           | 1,446           | 1,446 | 131 |   |
| Goodwill acquired                                                                                           |           |           |            |   | 1,313 |   |
| Goodwill decrease from divestitures                                                                         |           |           |            | 0 | 0 |   |
| Currency translation adjustments                                                                            |           |           |            | (1) | 2 |   |
| Impairment of goodwill                                                                                      |           |           |            | 0 |   |   |
| Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed) |           |           |            | 33 |   |   |
| Goodwill, Ending Balance                                                                                    | 1,478          |           |            | 1,478 | 1,446 | 131 |
| Electronic Systems                                                                                          |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill, Beginning Balance                                                                                 |           |           | 1,718           | 1,718 | 85 |   |
| Goodwill acquired                                                                                           |           |           |            |   | 1,632 |   |
| Goodwill decrease from divestitures                                                                         |           |           |            | (61) | 0 |   |
| Currency translation adjustments                                                                            |           |           |            | (28) | 1 |   |
| Impairment of goodwill                                                                                      |           |           |            | 0 |   |   |
| Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed) |           |           |            | 21 |   |   |
| Goodwill, Ending Balance                                                                                    | 1,650          |           |            | 1,650 | 1,718 | 85 |
| Critical Networks                                                                                           |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill, Beginning Balance                                                                                 |           |           | $ 2,424         | 2,424 | 1,056 |   |
| Goodwill acquired                                                                                           |           |           |            |   | 1,424 |   |
| Goodwill decrease from divestitures                                                                         |           |           |            | 0 | (24) |   |
| Currency translation adjustments                                                                            |           |           |            | (40) | (32) |   |
| Impairment of goodwill                                                                                      |           |           |            | (290) |   |   |
| Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed) |           |           |            | (28) |   |   |
| Goodwill, Ending Balance                                                                                    | 2,066          |           |            | 2,066 | $ 2,424 | $ 1,056 |
| Aerostructures                                                                                              |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Goodwill decrease from divestitures                                                                         | $ (61)         |           |            |   |   |   |
| Harris CapRock Communications                                                                               |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Impairment of goodwill                                                                                      |           | (290)          |            |   |   |   |
| Impairment of goodwill and other assets                                                                     |           | $ (367)        |            |   |   |   |
| Harris CapRock Communications | Critical Networks                                                           |           |           |            |   |   |   |
| **Changes in the carrying amount of goodwill**                                                              |           |           |            |   |   |   |
| Impairment of goodwill and other assets                                                                     |           |           |            | $ (367) |   |   |

| X                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Goodwill Decrease from Divestitures
+ References
No definition available.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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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.
+ References
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| - Definition
Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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