| **GOODWILL - Narrative (Details) $ in Millions**                                             | 3 Months Ended | 12 Months Ended |
|----------------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Finite-Lived Intangible Assets [Line Items]**                                              |           |            |   |   |
| Number of operating segments | segment                                                       | 3              |            | 4 | 3 |
| Number of reportable segments | segment                                                      | 3              |            | 4 | 3 |
| Disposal group, held-for-sale, not discontinued operations | CPS business | Aviation Systems |           |            |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                              |           |            |   |   |
| Goodwill assigned to disposal group | $                                                      |           | $ 174           |   |   |
| Goodwill impairment | $                                                                      |           | $ 62            |   |   |

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| - Definition
Amount classified as goodwill attributable to disposal group held for sale or disposed of.
+ References
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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.
+ References
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.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.
+ References
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| - Definition
Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
+ References
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| X                                                                                                                                           |
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