| **ACQUISITIONS, DIVESTITURES AND ASSET SALES - Acquisition of TDL - Narrative (Details) - USD ($) $ in Millions** |         |         | 3 Months Ended | 9 Months Ended |          |
|-------------------------------------------------------------------------------------------------------------------|---------|---------|----------------|----------------|----------|
||
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Goodwill                                                                                                          |    |    | $ 20,736       | $ 20,736       | $ 20,736 | $ 17,283 |
| CS                                                                                                                |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Goodwill                                                                                                          |    |    | 4,913          | 4,913          | 4,913    | $ 3,796 |
| Secured Debt | Term loan, due November 21, 2025                                                                   |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Debt instrument term                                                                                              |    | 3 years |           |           |     |   |
| Secured Debt | Term loan, due November 21, 2025 | Line of Credit                                                  |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Debt issued                                                                                                       |    | $ 2,250 | 2,250          | 2,250          | 2,250    |   |
| Tactical Data Links (TDL) Product Line                                                                            |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Purchase price                                                                                                    | $ 1,958 |    |           |           |     |   |
| Provision for loss on customer contracts                                                                          |    |    | 86             | 86             | 86       |   |
| Loss provision amortization expense                                                                               |    |    | 15             | 29             |     |   |
| Total liabilities assumed                                                                                         |    |    |           | 64             | 11       |   |
| Revenue from amortization of off-market contract liability                                                        |    |    | 7              | 22             |     |   |
| Future estimated revenue from the amortization of off-market contract liabilities, remainder of fiscal year       |    |    | 11             | 11             | 11       |   |
| Future estimated revenue from the amortization of off-market contract liabilities, year one                       |    |    | 22             | 22             | 22       |   |
| Goodwill                                                                                                          | $ 1,117 |    |           |           |     |   |
| Acquisition related costs                                                                                         |    |    | 10             | 64             |     |   |
| Tactical Data Links (TDL) Product Line | CS                                                                       |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Goodwill                                                                                                          |    |    | $ 1,117        | 1,117          | $ 1,117  |   |
| Tactical Data Links (TDL) Product Line | Other Accrued Liabilities                                                |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Total liabilities assumed                                                                                         |    |    |           | 33             |     |   |
| Tactical Data Links (TDL) Product Line | Other Noncurrent Liabilities                                             |    |    |           |           |     |   |
| **Business Acquisition [Line Items]**                                                                             |    |    |           |           |     |   |
| Total liabilities assumed                                                                                         |    |    |           | $ 31           |     |   |

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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
This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.
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Face (par) amount of debt instrument at time of issuance.
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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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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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