| **GOODWILL AND OTHER INTANGIBLE ASSETS - Narrative (Details) $ in Millions**                                                                 | 3 Months Ended | 6 Months Ended | 12 Months Ended |        |
|----------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|--------|
||
| **Finite-Lived Intangible Assets [Line Items]**                                                                                              |           |           |            |   |   |   |
| Number of reporting units | unit                                                                                                             |           |           | 8               |   | 9 |   |
| Reallocation of goodwill in business realignment                                                                                             |           |           | $ 0             |   |   |   |
| Goodwill                                                                                                                                     | $ 18,417       |           | 18,417          |   | $ 17,283 |   |
| Amortization of acquisition-related intangibles                                                                                              | 173            | $ 151          | 338             | $ 303  |   |   |
| Impairment of intangible assets                                                                                                              | 21             | $ 0            | 39              | $ 0    |   |   |
| Tactical Data Links (TDL) Product Line                                                                                                       |           |           |            |   |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                                                                              |           |           |            |   |   |   |
| Goodwill                                                                                                                                     |           |           |            |   |   | $ 1,117 |
| SAS                                                                                                                                          |           |           |            |   |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                                                                              |           |           |            |   |   |   |
| Reallocation of goodwill in business realignment                                                                                             |           |           | 327             |   |   |   |
| Goodwill                                                                                                                                     | 6,107          |           | 6,107           |   | $ 5,778 |   |
| Discontinued Operations, Disposed of by Means Other than Sale, Abandonment | Open Water Power Facility | In-process research and development |           |           |            |   |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                                                                              |           |           |            |   |   |   |
| Impairment of intangible assets                                                                                                              | $ 21           |           | $ 21            |   |   |   |

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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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| - 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.
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| - Definition
Amount of transfers into (out 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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| - Definition
Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.
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| - Definition
Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.
+ References
No definition available.
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