| **BUSINESS SEGMENTS - Geographic Information (Details) - USD ($) $ in Millions**    | 6 Months Ended | 12 Months Ended |
|-------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | $ 173          |            | $ 161 | $ 136 | $ 119 |
| Depreciation and Amortization                                                       | 442            |            | 258 | 259 | 311 |
| Revenue                                                                             | 9,263          | $ 3,208         | 6,801 | 6,168 | 5,897 |
| U.S. operations                                                                     |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 8,485          |            | 6,530 | 5,854 | 5,637 |
| Long-lived assets                                                                   | 1,865          |            | 866 | 892 | 896 |
| International Operations                                                            |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 778            |            | 271 | 314 | 260 |
| Long-lived assets                                                                   | 252            |            | 28 | 8 | 8 |
| Discontinued Operations                                                             |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 0              |            | 0 | 0 | 4 |
| Depreciation and Amortization                                                       | 0              |            | 0 | 0 | 39 |
| Integrated Mission Systems                                                          |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,774          |            | 48 | 45 | 38 |
| Integrated Mission Systems | U.S. operations                                        |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,300          |            | 30 | 39 | 27 |
| Integrated Mission Systems | International Operations                               |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 474            |            | 18 | 6 | 11 |
| Communication Systems                                                               |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,151          |            | 2,208 | 2,015 | 1,891 |
| Communication Systems | U.S. operations                                             |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 1,518          |            | 1,281 | 1,031 | 880 |
| Communication Systems | International Operations                                    |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 633            |            | 927 | 984 | 1,011 |
| Aviation Systems                                                                    |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,038          |            | 672 | 668 | 697 |
| Aviation Systems | U.S. operations                                                  |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 1,514          |            | 644 | 627 | 647 |
| Aviation Systems | International Operations                                         |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 524            |            | 28 | 41 | 50 |
| Other non-reportable business segments                                              |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 23             |            | 165 | 148 | 121 |
| Operating segments | Integrated Mission Systems                                     |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,774          |            | 48 | 45 | 38 |
| Operating segments | Integrated Mission Systems | Continuing Operations             |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 29             |            | 1 | 1 | 0 |
| Depreciation and Amortization                                                       | 37             |            | 2 | 2 | 2 |
| Operating segments | Space and Airborne Systems                                     |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,360          |            | 3,715 | 3,304 | 3,156 |
| Operating segments | Space and Airborne Systems | Continuing Operations             |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 36             |            | 48 | 49 | 49 |
| Depreciation and Amortization                                                       | 31             |            | 50 | 54 | 55 |
| Operating segments | Communication Systems                                          |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,151          |            | 2,208 | 2,015 | 1,891 |
| Operating segments | Communication Systems | Continuing Operations                  |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 22             |            | 29 | 25 | 16 |
| Depreciation and Amortization                                                       | 32             |            | 49 | 54 | 60 |
| Operating segments | Aviation Systems                                               |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | 2,038          |            | 672 | 668 | 697 |
| Operating segments | Aviation Systems | Continuing Operations                       |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 64             |            | 54 | 37 | 22 |
| Depreciation and Amortization                                                       | 53             |            | 29 | 22 | 5 |
| Operating segments | Other non-reportable business segments | Continuing Operations |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 0              |            | 6 | 4 | 1 |
| Depreciation and Amortization                                                       | 0              |            | 3 | 5 | 8 |
| Corporate eliminations                                                              |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Revenue                                                                             | (83)           |            | (7) | (12) | (6) |
| Corporate eliminations | Continuing Operations                                      |           |            |   |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |            |   |   |   |
| Capital Expenditures                                                                | 22             |            | 23 | 20 | 27 |
| Depreciation and Amortization                                                       | $ 289          |            | $ 125 | $ 122 | $ 142 |

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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.
+ References
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| - Definition
Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.
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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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