| **BUSINESS SEGMENTS - Additional Information (Details) $ in Millions**                     | 3 Months Ended | 6 Months Ended | 12 Months Ended |
|--------------------------------------------------------------------------------------------|----------------|----------------|-----------------|
||
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Number of reportable segments | segment                                                    |           | 4              |            |   |   |
| Number of operating segments | segment                                                     | 4              |           |            |   |   |
| Amortization of intangible assets, debt premium, debt discount and debt issuance costs | $ |           | $ 285          | $ 120           | $ 116 | $ 125 |
| Geographic Concentration Risk | Total Revenue                                              |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 5.00%          | 5.00%           | 5.00% | 5.00% |
| Government Contracts Concentration Risk | Total Revenue                                    |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 73.00%         | 77.00%          | 75.00% | 74.00% |
| Product Concentration Risk | Total Revenue                                                 |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 21.00%         | 22.00%          | 23.00% | 25.00% |
| Export revenue | $                                                                         |           | $ 2,000        | $ 1,500         | $ 1,400 | $ 1,500 |
| Product Concentration Risk | Sales revenue service | Integrated Mission Systems            |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 32.00%         |            |   |   |
| Product Concentration Risk | Sales revenue service | Space and Airborne Systems            |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 16.00%         |            |   |   |
| Product Concentration Risk | Sales revenue service | Communication Systems                 |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 15.00%         |            |   |   |
| Product Concentration Risk | Sales revenue service | Aviation Systems                      |           |           |            |   |   |
| **Segment Reporting Information [Line Items]**                                             |           |           |            |   |   |
| Concentration risk percentage                                                              |           | 39.00%         |            |   |   |

| X                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortization of Intangible Assets and Amortization of Debt Issuance Costs and Discounts
+ References
No definition available.
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| X                                                                                                                                                                                                                  |
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| - Definition
Export Revenue.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
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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
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                            |
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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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| X                                                                                                                                                                     |
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| X                                                                                                                                                                  |
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| X                                                                                                                                                               |
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| X                                                                                                                                                            |
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| X                                                                                                                                                       |
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